Does anyone have any idea how long a game stays in the game pass or is it different? And if I played a game in the game pass but I want to get the physical version, will my progress remain or not?
Until the game pass has expired
I mean games are removed too. Is there a certain period of time or is it different?
Differently
OK
Microsoft titles stay forever all other games are usually available for several months. I can't say more precise but there's enough time to play extensively.
You will also be informed beforehand via the app which games will be released and which new ones will be added. If you want to continue playing, the game will of course be retained and there are always attractive discounts on expired titles.