BIOS IS NOT UEFI! Solve the problem

In my Toshiba laptop, when I try to boot using external boot I get the error message:

The problem solved after I change  Boot mode  in System Configuration menu in BIOS setting.

Restart the Toshiba laptop and go to the BIOS menu, (press F2 key many times during computer up)
Make Disable the Secure Boot

Go to System Configuration menu
Change the  UEFI Boot to CSM Boot to allow the system to boot from external devices