For installing a new operating system or as we will need to found boot options of our PC.By boot option we can install is from our desired USB Device or DVD-ROM.So we will need to know how we can find a boot option on our different brands of PC.
So lets start,



                  Brand 
         Boot option Key
  BIOS OR UEFI option Key
Asus(Laptop)
Esc
Delete
Asus(Desktop)
F8
F9
Acer
Esc,F9,F12
Del,F2
HP
Esc
Esc,F1,F10
Dell(Desktop)
F12
F2
Dell(Laptop)
F12
F2
NFC
F5
F2
Intel
F10
F2
Compaq
F9,Esc
F10
Lenovo(Laptop)
F12
F1
Lenovo(Desktop)
F8,F12,F10
F1,F2
Samsung
F12,Esc
F2,F10
Sharp
F1, F10
F2
Toshiba
F12
F2
Sony
Esc,F10
F2
Fujitsu
F12
F2
Shuttle
F2
Del,F2
Gateway
F1
Del,F1


After all, when you start your computer then you can show the keyword for accessing Boot option and Bios.