The Steam Deck having the same hardware as a PC can run Windows 11 and Windows 10. There are two ways to achieve this:
- Wipe the device and install Windows.
- Install Windows on to an SD card and boot from it.
The main reason someone would install Windows on the Steam Desk as the default OS is a version of Linux that uses a Windows compatibility for games that isn't as good as it could be.
The drivers below are the intended drivers for Windows 11 & 10, there is more information on Steams site.