Everybody and their mother will have recommendations on their favorite flavor of Linux, but as somebody else about to make the switch with similar priorities as you, I’d suggest also taking a look at Bazzite. It’s built on the same distro as the SteamOS and comes in at least two flavors for what your use case is. One of its selling points is that it’s an “immutable” version of Linux, which means that it’s a lot harder to accidentally break it as a new user.