Several questions about USB partitioning and Windows Bootcamp

Do I need to partition a USB flash to back up files via Time Machine and also use Windows Bootcamp on the same drive? I’m on a 2015 (iirc) Intel iMac (macOS Montery Version 12.7.6) with a 256 gb USB stick and I am trying to use Bootcamp to run Windows-based games, but I’m slightly worried about losing some photos. Also, would Bootcamp even be able to affect any files on the 1 TB SATA disk that those photos are stored on or am I being a worrywart? Sorry if I’m asking too much in one discussion lol