This Ubuntu 21.04 PC never had dual boot, yet GRUB loads when I press F12 to get to the boot choices. I am trying to boot from DVD but can’t seem to get beyond GRUB which does not have the choice to boot to DVD. Do I just uninstall GRUB or is there some other way to deactivate it?
Even though the BIOS has the DVD as the first boot device, GRUB still seems to take over so the only way to boot to the media was to completely remove the hard drive from the boot choices. This is something I’ve never ever had to do in decades of PC work!
The mystery that I am asking about is that F12 typically opens the BIOS boot menu and GRUB never appeared until I used F12 the first time but now F12 brings up GRUB every time.