I am pretty much a click and hope it works type. Not a computer programmer or expert. I set up a groups.io that is mostly wiki with lots of clickable links for community information. I did one as announce only so that could have it publicly viewable for folks interested in moving to the area.
We set up another groups.io that is residents (members) only for a discussion area.
And a table of content wiki links there. It provides them with access to the wikis. It does not sound like you would need to have yours in different groups. So it would be one site.
You can look at the public one, which is a lot of wiki.I am sure there are better ones. But since it is for a community, might be similar to what you are hoping to do. I still have a lot of work to clean it up. Got so busy right away with COVID related information and coordination for the community on our the new groups discussion site. (it is a large one) and help with Nextdoor site.
I tried to use links rather than files in our wiki site where possible. Like links to county documents pages. In many ways I think better than uploading files. The link goes to their site and it keeps it up to date that way. Otherwise have to worry about having old file. They have to join ours for access to the files. You can see how some of the wiki looks. If it helps you to see something that is almost all wiki. Your wikis could be on your one site.