My last groups DM had to stop we disbanded for awhile.  I joined a new group but have been met with a DM reluctance.  I used to DM back in Ad&D but this will be my first into 5e.  I have played 5e for a bit so I'm good there.  My question related to using DNDB campaign.  I am trying to set this up but i don't know how to include a purchased adventure.  I can read them all day but how to i add it to the "My Campaign section so i don't show everything to players?  Is the a walkthrough or some set up guides anywhere?  Any help is appreciated as i am a last minute change and we are looking to start within a week and i need some prep.

Just a question here. What are you trying to do by adding it there? Are you trying to give them access to items or features from it? 

I am not sure adding it to the campaign does anything outside of just giving them access to those sorta things. Are you looking for a place to put maps and actually play on?

looking to provide access yes but also to provide the maps and such.  I know roll 20 does that sort of thing but I am not sure if DNDB does.  If not the my campaign is kind of useless.  I can create and add characters in roll 20 as well as have a greater access to books and resources.

You can save the maps and upload to roll20, but there is not automatic importing or anything.

To be clear, roll20 and DDB are competitors, so it's not really in their interest to share content that users pay for. I believe most people who use both sites tend to pay for content here and connect PCs and NPCs through the Beyond20 plugin. While it's true that you can do it all in roll20, I find the character building process to be a lot smoother and more user-friendly here.

Quote from Whiterquick >>

looking to provide access yes but also to provide the maps and such.  I know roll 20 does that sort of thing but I am not sure if DNDB does.  If not the my campaign is kind of useless.  I can create and add characters in roll 20 as well as have a greater access to books and resources.

 You can provide access to your compendium and your character builder options. Thats absolutely fine. You can also provide access to magic items and the like. 

But DNDbeyond is not a VTT. You can likely copy and paste the maps to the players, or copy the maps to a VTT that way. But there isn't a way to set up tokens or anything like that Roll 20 does. They do different stuff

So, the point of the My Campaigns section in D&DBeyond is to have one place for character sheets to be seen by the DM, most DM's/groups have at least one master tier sub which allows the option for content sharing (once activated any content owned by anyone in the campaign is automatically shared) so that players/DMs have the ability to view anything owned/use them for character sheets.

Yes, you could just build your characters on Roll20, though if you own the books here, but not there, well I've found the character sheet builder on Roll20 to be...lackluster personally.

For maps, as stated, you can save them and use them on Roll20, or other VTT options. D&DBeyond does not have a VTT option.

Also, personal note for why you would want character sheets here vs roll20. I can easily look my character sheet up on my phone, either through the dndbeyond app, or web browser.
Roll20 doesn't open on a phone, and looking at your character sheet, personally is a pain for Roll20, needing to open the site, open the campaign, wait for it to load (only available on PC as well) limits the ability to edit/lookover things if you don't have access to a laptop/tablet/pc.

And if for some reason the campaign ends, or you leave, (or get kicked) there's no easy way to take your character sheet "with" you. As opposed to dndbeyond where you just click "leave campaign" and your character sheet is still accessible.

If you're looking for a free option to share with your players "old school" I recommend Owl Bear Rodeo:  https://www.owlbear.rodeo/

You have to upload the maps yourself but it's quick, it's easy and it's free.  For my streamed games I've 100% moved to it and while my players lament the lack of Roll 20's intergration I'm going to stick with my current set up of DND Beyond for sheets, Owlbear for VTT and Zoom for meeting.

I also use Improved Initiative for combat tracking: https://www.improved-initiative.com/e/