If your computer is a new computer and you are unsure of what key to press when the computer is booting, try pressing and holding one or more keys the keyboard. This will cause a stuck key error, which may allow you to enter the BIOS setup.
On BIOS Setup menu, You will Found Advanced BIOS Features, move your cursor to fill the Advaced BIOS Features then press Enter. Move cursor to First Boot Device and use + or - keys to make change to CD-ROM. Press Esc key and F10 key to save settings and reboot your computer automaticly.
To boot from the computer simply place the bootable CD or DVD into the CD-ROM drive, reboot the computer and the computer should detect the bootable CD and boot from the disk.