Understanding ActivityPub and Federation

I have tried to understand how Federation works but I'm getting a feeling that there's some rather large gaps here. My first attempt was to find an API implementation in python, 3 wasted hours of my life later and I'm making requests.request() calls like it's 2007. And I still can't access the content as presented on the webinterfaces. There doesn't seem to be a way to access eg the communities tab via activitypub? Any Help?

@programming