1.Check if the USB drive contains a bootable operating system.
2.Ensure that the latest version of BIOS is installed on your computer.
3.Check the boot order in the BIOS settings to make sure that the USB drive has been placed first.
4.Change the USB port to which the USB drive has been connected and try again.
5.Flip the BIOS switch to Legacy mode, if your computer is configured in UEFI mode.
6.Try to use a different USB drive if the issue persists.