I'm thinking about going home I just don't know if and how long I would have internet access there.
Hence my question, if I would do it and had no internet I could still play a PC game from Steam, Epic or the Game Pass beta PC Xbox which I have downloaded onto my computer or is generally internet access mandatory for all games today?
I'm looking forward to your answer
At least Steam runs offline without any problems.
Most of such services require at least to install / activate internet. After that, they can actually be played offline without any problems
You don't need internet for offline mode (Steam, Xbox). With Steam you can also log in without an internet connection if you have already logged in with the account on the device. The Xbox stores as much as I know the access data - I haven't tried logging in there without the Internet, but it should work. You can simply switch off your network for a test. Then you see what's still going on and what's not.