I want to dm for the first time. I am hoping to do it online or in person.

I don't have mini figures and anything for in person games. I done online stuff before and it isn't easy to making up a whole storyline. I do have a dm who is willing to help me since I do go somewhere to play dnd. I just want to know which one is better for someone who is neurodivergent and who is dming for the first time.

"Neurodivergent" is a pretty broad term, and without knowing more about you personally it's hard to give good advice on that front. However, there are definitely advantages to doing it online:

• You don't need any physical props or materials
• You can do it from a location that's comfortable for you
• The other people don't have to see you if you don't want them to
• You can play with people located anywhere in the world
• It's often a lot easier to schedule

I think it's safe to say that neither is objectively better. People have different opinions, for example I far prefer in person, but neither one is simply better or worse. It's entirely about what you like. If it helps, here are a few different things to consider:

- Do you know who you're playing with yet? That can decide this issue for you. If you're looking for a group, online can certainly make it easier to find people. And if your group isn't all local, then you'll just have to play online. But if you already have a group, or even a local community, I'd start by asking what they want to do. 

- Playing online vs. in person is absolutely very different, but I don't think there's a meaningful difference between the experience as a DM vs. a player. If you have a preference as a player, that's probably how you'll enjoy DM'ing too. 

- I don't think tabletop sites make it easier to learn how to be a DM. That's still just about settling in to read the DM Guide, then reminding yourself that everyone learns how to do this through trial-and-error. To be fair, most sites do offer lots of tools, but I've always found the benefits pretty marginal. I still have to know the rules and run the game myself. In part that's because any tabletop site that enforces specific rules would limit your flexibility as a dungeon master, and I'd strongly recommend against that. 

 - You don't need minis, or almost anything else, for an in-person game. Just the character sheets and your books (whether physical or digital). While minis can be cool and cinematic for a combat encounter, you definitely don't need them. Heck, you can do combat encounters full theater-of-the-mind style if you'd like, meaning you just describe everything as it happens. I've run plenty of games that way and it works great. 

- If you want to visualize encounters, it can certainly help to have a grid and some tokens. But those can be very simple and inexpensive. I use the D&D whiteboard material grid ($25 at my local comic shop) and a stack of small whiteboard discs ($18 on Etsy), so we're just sliding simple discs around an undecorated grid. If you want something even easier, anything will do. You can just draw up a grid on some paper and use whatever tokens are handy. Minis are, really, just decorations. Cool decorations, to be sure, but very few players will actually care if you don't have them.

- But, tabletop sites definitely can give you access to much cooler visuals very easily. It's certainly a lot of fun to have the orcs look like orcs, and to have your sorcerer lay down a cone of illuminated fire. So that can be worth it on its own!

- However, playing online is (in my experience) a lot less social. It's the difference between a Zoom call and seeing someone in person. I find that the game flows more easily and people interact more naturally in person than online. 

- I don't think either in person or online is going to matter for writing the story. That's the same project no matter how you're playing. It definitely isn't easy, and writing an entire campaign is a TON of work. Most people recommend that you start by purchasing a pre-written campaign, so you have a sense of how it all fits together before trying to write your own. Either way, your format won't change that up. It will still be about just sitting down and writing your story. 

- Again, take this with a grain of salt because personally I very strongly prefer in person play. However, if anything, I think online formats can make it harder for a first time DM. In addition to learning all the rules and mechanics of D&D, you also have to learn how to work the tabletop site (and a lot of these can get super complicated). Personally, if in person is an option, I'd suggest that it would be a lot easier to run your first couple of sessions that way just so you only have to learn one thing at a time.

I'm afraid I can't help with which would be better for neurodivergence. Sorry! But I'm excited you're starting up. Good luck and have fun!

Personally, i prefer playing online. not only am i able to prevent my players from seeing my face if i want to, but i can modify my voice and create entirely new voices for characters with minimal effort on my end.
That's not to say playing in person is bad, of course! it can be fun to become immersed in a storyline. but if youre not the best at RP (like me) then it can be a bit stressful, especially with everyone doing voices and acting things out dramatically and loudly. (i suck at volume control)

As someone with ADHD and ASD, i find it easier to play online. minimal stress, i can play and DM from anywhere i'm comfortable, and it is so, so much easier to schedule things. I'm unsure what flavor of neurodivergent you are, but as a DM with neurodivergence, that's what i find helpful about playing online.

of course, playing in person has its benefits too. you can get immersed in the plot and character, it's a good chance to meet up with friends, and it can be really fun having a particular setup like a DM board, minis, and a couple laptops set up.
I know that a few friends and family members of mine that play dnd also meet up in person AND play online (at the same time.) this requires no minis and allows for the in-person roleplay and hanging out (and sharing snacks)

in short: Do what makes you feel comfortable with your setup and skills!! and, i CANNOT stress this enough-- always have snacks on hand.

Ereed suggested Theater of the Mind for in-person games, and I just wanted to add you can do that for online games as well. That's how I run my game, and if things start to get complicated or distance matters, I pull out Microsoft Paint for a quick sketch. (I am not an artist, this does not look pretty, but that's okay.) I did try out a VTT for the first time for the final boss battle last session, but I just screenshared it with my players and moved all the tokens myself. Kind of cool for the finale, but not something I'd want for every single session.

On making up a storyline, the recommendation you'll get from most people is don't. Those who prefer storylines tend to recommend starting with a published adventure. Those of us who like to write our own tend to go for more player-driven stories where you only prep what happens next rather than having an overarching plot. Either way can give you a fun adventure, depending on what you and your group prefer.

Hope it goes well for you!