The transition won't be painless. You're going to have to learn new things, especially if you're familiar with the windows file system and how to work within that.
Linux doesn't use "drive letters" for mount points, so you'll have to learn that.
Many games through steam or other game managers are just as easy if not easier than in Windows. Some are more challenging.
If you're tired enough of Windows that you're willing to push through some discomfort and new learning, then it's time.
Once you get to know the distro you choose (Ubuntu is fine), you'll just work, and it won't get in your way.
That's great to hear! Welcome, and have frustrating fun!
If you don't mind me asking; in your context, what does "leftist" mean? When I hear the term, it's usually meant as a pejorative for some nebulous group the utterer doesn't like.