Aorus B550 Elite AX V2 - this motherboard?
what do blue lines look like? can you share some screenshots?
manual -
https://download.gigabyte.com/FileList/Manual/mb_manual_b550-aorus-elite-ax-v2_e.pdf
i don't think usb should be in boot sequence at all, it should be empty if the motherboard is brand new.
really, on a new mb you shouldn't have to do anything in bios, it should just boot off the USB
Gigabyte boards have a choice on the Save & Exit screen called Boot override, I would try to use it
put USB in at boot (I have a Gigabyte Aorus X570 so its going to have the same menus)
reset bios to defaults
go to save & exit screen & choose boot over ride
pick the UEFI USB choice here and PC should restart and boot from USB
Where did you get win 10 installer from? If its not new, On another PC, download the
Windows 10 media creation tool and use it to make a win 10 installer on USB (A new version is win 10 is due out in the next few days/weeks but this will at least get you the November version)