I’m pretty fresh to Linux myself, but as far as I know it’s exclusive to steam. You can launch non-steam stuff through it by adding the .exe to the Steam client, I played Fallout 1 this way

For real. I’ve been vegetarian for a few years now and of all the things I kind of miss, not once has bacon been even a slight craving. A good kebab on the other hand…

If you don’t have prior experience with Linux, I’d advise making the switch before the end of win10 support. I made the switch a couple of months ago with no experience in Linux, and while it wasn’t a horrible experience it also wasn’t the easiest thing to do. Having the safety net of a Windows partition was really useful during the month or two as I got used to Linux, which I wouldn’t have wanted to do with Windows not in support anymore.

I made the switch 2-3 months ago, and I went with Kubuntu. It’s absolutely fine, but if I knew then what I know now I’d likely have gone pop or mint, just to not bother with snaps (although they’re pretty easy to get rid of).

As others have said, get Ventoy on a USB stick, use that to have a play with a few live environments and get a feel for what desktop environment you might want to use. KDE and Cinnamon I think are pretty good Desktop Environments if you’re used to Windows, but have some fun with it and also try a few that are very different to windows, you might find yourself liking them (I really like using i3 on my laptop where the screen is fairly low res)