The BIOS (Basic Input Output System) primarily responsible for starting the operating system and the functioning of the PC. Therefore, the BIOS controls the interaction between the individual hardware components of the computer.
In case you have to start the computer from a different medium, you have to change the boot sequence in BIOS first.
1. Restart your computer.
2. When your computer starts up, the boot screen shows the required key or key combination to access the BIOS. (This varies depending on the motherboard manufacturer.) The most frequently used keys are: Delete, F1, F2, F8, or F10.
3. As soon as you see this, tap the required key repeatedly.
4. The BIOS interface usually opens in a shade of blue. (you can only navigate the BIOS menu using the keyboard).
5. Change the boot sequence (CD-ROM Drive or Removable Devices) according to the medium you want to start the computer.
6. Save your changes and restart the computer.
The computer will now start according to your configured boot sequence.
Connect the required medium to the computer to boot from it.