So the problem is that whenever I press play in Skyrim menu it says my game version is not supported and I dont know why since I played the game 3 weeks ago with no problem, I tried reinstalling but it doesnt work, can someone help please? And I couldnt find a way to get a working patch.

You've got an outdated script extender, SKSE or Script Dragon. Either update them or remove them. It's not an issue with Skyrim at all.