Alright! 

So, me and four friends finally decided that we are going to start playing. I've been watching hours of play through Critical Role but only played a couple of times myself, and that was years ago. Still, it ended up with me as DM and I'm so gosh-darn exited! 

It was complicated to start planning this thing, and while I'm far from 'done' I feel like I'm on the right track. I guess the point of this thread is to create an overview of what to do for those in the same situation as me, and below I'll write down what I have done, or is going to do, in an (attempted) orderly fashion. 

First a summary of what I think I need, then in a little bit more in detalj surrounding how I think the game will play out. 

At Game Night - List

This is the list of what I think I need at game night. First really important stuff, then things that would be cool to implement

Important:

• A plan! Have a vague, or precise, idea of what to do for this session. Encounters/NPCs/pacing - But be prepared to be unprepared!
• Dice! With spares!
• Notebook and pen - to keep track of Initiative, improvised statements
• My Laptop - to search up whatever I forget to prepare
• A GM-screen with the following information
  • Player Character-sheets
  • Monster encounter sheets
  • NPC sheets and notes
  • Combat rules

- Dice from eBay
- Monster sheets found online (carefull to give the Player overpowered monsters - if needed I'll nerf the monsters I pick)
- GM-screen example: https://imgur.com/a/IXjjg

Cool to have

• Battle-map (this might even be a must)
• Miniatures
• Extra encounters. In case the Players decides to just do something really strange
• Music for the following places/activities  
  • Traveling
  • Cave exploring
  • Battle
  • City-sounds
  • Tavern
• Also, I know there are apps to help with the game, but I haven't studied any of them in detalj.

- I made the battlemap myself, but you can check out this site for inspiration:
https://donjon.bin.sh/

- Miniatures is expensive! But if you have access to a printer and dont mind paper-miniatures you can check out this site: (otherwise you can use any little trinket to symbolize a character or monster)
https://printableheroes.com/minis#

- Music can be found on Spotify and/or youtube. But prepare a playlist! Don't waste time looking up 'that perfect track'.

Where to start? - World building

O'my! At the start my thoughts were scattered at best. But luckily I found this site that generates a Fantasy World-map, and suddenly I had something to look at. And with that, things fell into place:

 https://donjon.bin.sh/fantasy/world/

Once I had generated a map I could start imagining the lore of the world. My map ended up with a large land/island with a mountain range in the middle. And in the middle of the mountain range there was a Stronghold! Obviously a home for Rock- and/or Hill Giants! 
And south of the mountains - a forest pre-named Faerie Woods. A perfect place for Encounter of the Week: Ensnared by Ettercaps!

https://www.dndbeyond.com/posts/455-encounter-of-the-week-ensnared-by-ettercaps

And if you want, you can edit the map in Paint. Add cities, rivers, lakes - or rename something to fit the world you want to build.

And so, I studied the map, took notes, and asked myself 
- Where the capital is?
- Where are points of interest?
- Where does the Big Bad-guy live?
- What is the relationship between the towns?
- How is the world run? 
- Is there a King? Or an elected leader?

and finally

- Where does the adventure start?

The Adventure starts

I figured that the first thing me and the players needed to do was to embark on a sort of turtorial level. Something a bit railroaded and straight forward, but still gives them a sense of freedom of choice. 
A small quest to a cave that goes through different skill checks and eventually a battle.

This was, and still is, what required the most thinking and planning,
but I've ended up with something like this:

The party starts in a carriage pulled by a horse. They've been hired to investigate an area a few hours west of the city as travelers and merchants have complained to the local Guard that the road is 'un-traversable'. The Guard did not have the manpower to deal with this them self and decided to hire the Players, and the Players needs the gold.

On their way they will meet:
- A small group of bandits. The bandits are utterly useless and can be easily killed and looted for a small amount of gold. But they can also be spared, something that will reward the players with information about the road ahead.

- A traveling merchant/trader on his way to pick up wares. He can be robbed for the little content he have, ignored, or talked to. He can decide to help the Players by  giving them a healing potion. Later, he might've set up shop in Town and can give the Players discounts.

Enter the Dungeon

The Players notices (passive- or active perception) that the trees and grass becomes more and more decaying as they travel. Soon they see a large, dead tree that marks the entrance of a crudely dug cave. Faint light comes from within.

I made a crude map of the cave consisting of three main rooms.
- First room, a large room with a few zombies/ghouls. Otherwise little of interest.
     - Down towards the second room a poorly made trap blocks their way.
- Second room, seems at first narrow, but consists mainly of a prison of sorts. Multiple corpses in the cell, and a single survivor. The Survivor can be saved (need to flesh him out a bit)
- Third room, boss battle. A strangely zombiefied Necromancer is there. The Necromancer is in what looks like a messy laboratory, filling a large cauldron with bodyparts. 
His main action is to summon 2 weak zombies, up to 3 times, visually using one out of three diamonds hanging by a chain around his neck each time.
He can be killed quickly to reward the Players with the unused diamonds.
When he is killed it is hinted that he was controlled by someone/something else
On the table in the center is a notebook with strange markings. 

This dungeon should cover the basics of play, and then some.

What next?

After picking up the reward the Real DnD Begins.

They can choose to bring the cryptic notebook to be deciphered. (This might be the "Main Quest")
- They need to bring the notebook to the library in the Capital, either via the mountains and the Giants Stronghold, or around the mountains and through the Faerie Woods.

They can travel west toward the coast (I haven't planned this out at all)
- They might hear talk about more Necro-related activity. 
- At the Coastal City there is some strange activity surrounding an orphanage

Stay in the Starting City and find out why the local Guard is spread so thin
- Haven't planned this one out either

Travel north
- Hopefully not... The Main Baddie is up there. Certain death, and all that... 

Comment, discuss, steal, criticize, and share ideas to your hearts content!

Are you using battlemat? For example: https://www.amazon.com/Paizo-Inc-PZOSQW30024-Pathfinder-Flip-Mat/dp/1601255381

Nope. Tried doing this as cheaply as possible. So I'm using  paper and a fat marker.

Each room on a different piece of paper, to be introduced as they travel further in.

Would you recommend a battlemat, though? 

I always have a list of 10 male names and 10 female names, because when players introduce themselves to random farmer 3 he is much more believable as Guss

OK - you do not lack for enthusiasm, and that's a good thing!

However, be careful you don't swallow the whole cow at once :)

I would recommend starting out as small as you can, with as little as you can; get used to that; add on as you can, until you reach the rich level of complexity and wonder that you want.

I think your game-night list is pretty spot on. If you're comfortable with doing it this way, I collapse everything into my laptop. My pre-game adventure notes are there, the notes I take during the game are there, even the blow-by-blow of combat tracking gets put there. It's even my rule books ( DnD Beyond ), and my DM screen. 

This also means that I can reach out and tap online tools if I need them in the middle of play: Kobold Fight Club and Donjon's 5e Encounter Calculator can help you gauge the size of impromptu encounters on the fly, RPG Tinker can help you whip up impromptu humanoid NPC stats pretty quickly, and I use the family of Fantasy Name Generators dozens of times in play ( it's replaced my "list of NPC names" ... OK, we're in Lucana, which is based on Renaissance Italy, so that wizard's name is ... *click* .... Salvi de Albvxiis ).

Since I'm tracking my campaign through DnD Beyond, and all my Players keep their live character stats in DnD Beyond - it means I have real-time access to their character sheets, stats, and HP.

This means I have one ultralight laptop, and a bag of dice to carry. That's it. However, some people like the pageantry of DM screen, the stacks of rule books ( and they do look cool, and there's something about the printed word ), binders of notes, etc. - so it's all a matter of taste. I tend to go functional over aesthetic.

As for battlemats and miniatures - they are not needed at all, although they are the usual approach, and many people prefer them. Have a look here, for the alternate - and much less complex and expensive - approach of using Theater of the Mind, or Abstract Maps instead. Personally, I use the Abstract Map approach, as it allow Players to easily grasp the spacial relationships, and rough distances, without slowing down combat with miniature setup, counting off squares, etc. 

However - many people don't think the game is the same without the battle-mat - use what works for you and your players.

So, as to prepping and running: you mentioned that you're running while being somewhat new to D&D - congratulations, and welcome to the hot seat :) 

As for world building - my advice would be: stop!

Don't invent any more than you absolutely need right now. I think you're thinking logically & practically about how your world goes together - no issues there - but maybe invert your approach.

Start with "Where does the adventure start?" It starts in a village? OK - you only need that village for now: A rough layout, a list of buildings that can found there, a description of the kind of people you can find there ( all humans? mixes species? Differing ethnic groups? ), an idea of the kind of culture, what god(s) do they worship ( and only sketch out those gods for now - you'll be inventing other's later, as you have time and need ). What kind of local government? Sketch out the local notable people; build in some interesting and detailed NPCs. Maybe put in some factions and groups. Build in some local rivalries and local conflict ( a clan feud between families? A friendly rivalry between local brewers? A secret cult worshiping some dark creature causing trouble in the town? ). Make some of the locations interesting and noteworthy. 

Now - build out from there a little bit. What are the surrounding natural features: the local forests? A lake? A moor? The trade road running through town? You'll need some of these to be possible sources of low-level adventure, so keep that in mind. The locals know about these - but they might not know everything about them.

How about some further off places: the next towns down the trade road, the city which is the Barony seat, the far off national capitol. Only sketch out as much detail as the local population would be able to tell the party - for now. Sketch out large general strokes about the land they're in - again, only as much as the locals would know for now. Also, wildly vague and probably inaccurate ideas and stereotypes of surrounding lands, and cultures.

Throw in some enticing legends and rumors that the locals would gossip about, and might interest adventurers to investigate: the far off Giant stronghold, the legend of the Faerie Queen of the eastern marches, the cursed mine deep in the hills of ...

The general idea here, is that you need to create details and specifics only for what the Players are interacting with - everything else is created with diminishing levels of detail ( and accuracy ) the farther away the players are from it. You'll sketch in the blanks and make those more detailed later, as they become closer and/or more important to what the Party is currently doing.

Build a rich, nuanced, and detailed world locally - and only as much detail as you need as you move out: Build richly, but not broadly.

I think your approach to an introductory adventure is very reasonable, and I think you've got a good sketch started.

A couple of - possibly controversial - comments here, though :) 

Don't build adventures in terms of video games. You hear it a lot in D&D circles, and it's why many people think of finishing an adventure with a "boss battle" - it's how video games are set up.

Perhaps think of adventures more in terms of literary setup.

• Create ( or find )  a point of conflict, or a "dramatic question" which includes some possibility of action: "who has been raiding the merchant caravans along the eastern road, and can someone stop them ( and claim the reward the local seneschal is offering )?" 
• Around that conflict, you list the parties involved in the conflict: The local merchant guild, the local bandits, the Players - and maybe others that are not as immediately obvious. You can be as sneaky and detailed as you wish.
• You sketch out the motivations, goals, resources, personalities, and knowledge of each party ( although the Players usually take care of their own - still, dangle the reward in front of them as possible motivation ).
• Then for each party involved, ask - "Given what they know, their resources, their goals, and their personality - what will they try and do next?"
• Figure out where those actions will collide, next - these are your encounters, to be resolved. Maybe the Players will charge out and fight the bandits ( combat encounter ), maybe they will try and convince the local bandits to give up the raids via persuasion or intimidation ( social encounter ), maybe the local bandits will be tipped off by the local bandit leader's brother ( working for the seneschal ) that the Players have been hired, and the bandits will try and kidnap the Paladin's sister to keep the Party at bay ( social encounter hostage negotiation, possibly followed by a combat encounter ), etc.
• Rinse, and repeat, until the original question has an answer, and the conflict between all the parties has stopped ( one side, or the other, had won - or everyone has stopped conflicting ).

This changes the plot from a pre-written script, into a chess game of move, counter-move - in "real time".

This is a more improvisational style, and it's not to everyone's taste, but I think it has some real benefits:

• You can put all your creative energies into making complex and interesting settings, NPCs, and situations, and not have to worry about writing a plot ( which your Players will ignore, and go and do something else, anyway ).
• It's organic, and realistic.
• Your Player can never go off the rails and charge into areas you hadn't planned to deal with ( and now you're panicking ) because a) you didn't plan anything and b) your whole approach is built around dealing with unplanned actions and events.
• You can easily incorporate Player ideas that they come up with.
• It's extremely flexible; with small changes in your initial setup you can spin out wildly different adventures. Consider the kind of adventure you are likely to have if the motives and causes you set up initially are different: The bandits are just in it for the money; the bandits are trying to destabilize the local seneschal by intercepting his tax payments to the kind and putting him in disfavor with the King; the bandits are being run by the seneschal , and they're stealing the money to fund the rebels against the King; the bandit leader is enthralled by a fey creature punishing the local seneschal, who has captured one of its people; etc. You have to expend very little in effort to make small changes in the beginning to make the unfolding adventure very different.

I'd also recommend you check out this guy: Matt Colville, and his Running the Game series on YouTube.

All in all, it sounds like you're off to a solid start.

Best of luck! :)

Thanks! It's actually really helpfull! 
You're right, I have been going about this in a "Video Game"-mindset, and it's actually really  liberating to shake that a bit off! 
And I'll probably read through your comment a dozen times.

Thanks again for your time
 - Ø