As raven said, it shouldn't matter much, and WINE/proton will do most of the work.
But I'd recommend something Debian-based, and specifically Ubuntu-based, because those are the most popular flavors, and thus the most likely to get proper testing. For reference, raven's rec of Mint is Ubuntu-based. Fedora is the second most common, so you're still likely to find good support. Arch or Gentoo are a lot more likely to require fiddling around to make things work, but honestly if you're installing one of those it's probably because you enjoy that sort of thing.
If you're buying hardware, AMD graphics cards have better Linux support in general, but Nvidia works well if you install the proprietary drivers (which is usually an extra couple of checkboxes on most distros).
As raven said, it shouldn't matter much, and WINE/proton will do most of the work.
But I'd recommend something Debian-based, and specifically Ubuntu-based, because those are the most popular flavors, and thus the most likely to get proper testing. For reference, raven's rec of Mint is Ubuntu-based. Fedora is the second most common, so you're still likely to find good support. Arch or Gentoo are a lot more likely to require fiddling around to make things work, but honestly if you're installing one of those it's probably because you enjoy that sort of thing.
If you're buying hardware, AMD graphics cards have better Linux support in general, but Nvidia works well if you install the proprietary drivers (which is usually an extra couple of checkboxes on most distros).