Some time you might want to boot your computer from cd/dvd rom for some reasons which I might not known, but here are the steps you can follow to allow your computer to boot from cd/dvd
1. press the start buttom
2. immediately you press the start buttom, continue pressing F9 untill the boot manager appears with a blue screen.
3. Press down to cd/dvd rom drive
4. And finally your press the enter key.
Hope this has help you
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