If you can’t choose, consider installing Windows 10 first, as this will leave you’re the option of updating to 11 at a later date.
OS: Don’t tell any Linux fans I said this, but if you just want an everyday gaming PC, Windows remains your best choice of operating system. As for which version, that’s your call: Windows 10 will possibly be more familiar, and lacks some of the more esoteric system requirements of Windows 11, but then the newer version has some gaming-focused features that 10 lacks. If you can’t choose, consider installing Windows 10 first, as this will leave you’re the option of updating to 11 at a later date.