u/EmbarrassedPurpose68

Hello, I recently built a new PC and when running a game, it warned I need to update the BIOS. I grabbed a flash drive, downloaded the BIOS files (BIOSRenamer and larger Z790 file) but I'm not sure which USB slot on the back is dedicated for BIOS updates? Checking online most comments say the slot has 'BIOS' above it or has a black/white/etc outline around it. I don't see any of this. Would anyone by chance be able to help? Thanks for taking the time.