Because no one addressed it yet, you won't be able to use Game Pass at all on Linux (unless you're using the streaming service). There's no way of making that work currently, and may never be a way. But for most everyone else? Most things just work out of the gate with no tweaking. But for things that don't, use https://protondb.com
Newsgroups binaries, typically on Usenet. Basically there are indexes of binary files posted on newsgroups across a huge distributed network. Typically you would pay an annual membership towards an index to be able to find content. You can run your own index too, but it’ll only cover anything newly posted and it’s worth paying for the historical things of 6+ years ago.