Dear,
I'm trying to install a clean image of Ubuntu 20.04 LTS on my laptop. I have created a USB startup disk and want to select that as boot startup option. However, USB is not shown as an option. I went back to boot default settings and tried again - no success. Then I enabled legacy mode, disabled secure boot, and moved USB to the top of the order in both UEFI and legacy startup orders. Still, USB does not show up in the boot device options menu.
Both boot USB stick and USB port work - I was able to verify that with a different computer and USB stick respectively.
I appreciate your help and suggestions to allow me to boot from USB.