I have a computer from HP(((((
All HP computers don't use the same key to access the BIOS so you might do an online search for your specific model. The F10 key is common so try rebooting the computer and when it is restarting, before you see anything on screen, begin tapping the F10 key and if you do access the BIOS, go to the Boot Options tab at the top using the arrow keys on the keyboard, then arrow down to OS Boot Manager to highlight it and hit the Enter key. This should open a small window which lists the various options. You can use the F5 key to move a highlighted entry down and the F6 key to move a highlighted entry up.
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