How to change boot priority sequence in BIOS Acer From UEFI to Legacy
During booting, keep pressing F2 key to enter BIOS settings. Use arrow keys to select menu item. Use F5/F6 to change values
(This is for Acer. You need watch the screen hints and follow the instructions in other brands,which might need to press F10, Del, or Esc to enter BIOS settings)