I also wants to do this!
Yes! The only resources I found are the official “tutorial” for it, but I am really a newbie, so I would like to have a kind of demo with a very basic code that I can test by myself. https://www.w3.org/TR/activitypub/
Oh ! Un francophone !
The link is broken
GitHub is owned by Microsoft so it’s not open-source, if you want an easy alternative to GitHub other than GitLab, Gitea is a great choice, this has a GUI like GitHub but it is open-source and it is easier.
You should really check out the link!..