Recovering a Linux root (or sudo user) password is pretty easy, but the hard part is getting into the BIOS if you have an Intel NUC PC.
The key combination that you should try is to repeatedly press
F12 and hope you see the menu.
Once you have the menu, press
e to edit.
Move to the line that ends with
ro quiet splash (it’s the long line) and remove the word
In place of that, rather put
rw instead of
ro and append this:
Now press Control+X (or F10) to boot.
You will see a prompt:
mount -n -o remount,rw /
now do this:
There we go, Bob’s your Uncle.