There may be a few reasons why you cannot see the option. First, is your current BIOS mode UEFI or legacy, since if you are in legacy mode, you will not see the UEFI option. Another thing you could try is disabling fast startup since sometimes that can affect being able to get into the UEFI firmware settings. Third, you could also try making a Boot to UEFI shortcut on your desktop, which may allow you to get into the UEFI firmware settings. Finally, if all else fails, you could try clearing your CMOS. This is what I would do, but I am no expert on this, so if anyone else has a better suggestion, please feel free to chime in.