Cant see USB device in BIOS bootable priority list

The USB device usually will not appear as a generic boot priority entry unless it contains valid boot media for the firmware mode the PC is using. On a Windows 11 system, the firmware is typically using UEFI, and the boot list may show only Windows Boot Manager (UEFI) until a bootable USB is detected.

Try this:

Confirm the USB is actually bootable.
A normal storage USB stick will not appear as a boot option. It must contain bootable media.
Open the one-time boot or firmware menu during startup.
Common keys are Esc, Delete, F1, F2, F10, F11, or F12. On many PCs, the startup screen briefly shows which key opens the boot menu or BIOS.
Look for a boot entry that includes both the device and firmware mode.
In the boot device menu, entries can appear as:
- UEFI: USB Drive
- BIOS: USB Drive
The same USB device can appear twice if both modes are supported.
If the PC is set up for Windows 11, prefer UEFI boot.
Windows setup is generally recommended in UEFI mode, which provides more security features than legacy BIOS mode.
If the USB does not appear, check whether Secure Boot or firmware settings are blocking that media.
Some devices only support one mode, and some only allow BIOS-mode boot after manually disabling UEFI security features under Security > Secure Boot. This is a firmware change, so use it only if the USB media is known to require legacy BIOS mode.
Do not use Add new boot device unless the firmware specifically requires a boot file.
That option is typically for manually browsing to a boot file. On older systems that support UEFI, the manual path can be:
\EFI\BOOT\BOOTX64.EFI
If installing or testing from USB, set the USB drive as the first boot option temporarily, or use the one-time boot menu instead of permanently changing boot priority.

If the USB was created for legacy BIOS only, it may not appear as a usable option on a Windows 11 UEFI configuration. In that case, recreate the USB as UEFI-bootable media and then check the boot menu again.

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