In order to boot from the USB / DVD we need to enable F12 boot menu and disable the 'Secure Boot' in the BIOS.
please follow the steps below:
1. Shut down the computer.
2. Press the power button, then keep pressing the F2 key until you are taken to the bios menu.
3. Under "Main" tab you will find an option called enable F12 boot menu, make sure it is set to enable.
4. Go the the 'BOOT' tab and set the 'Secure Boot' option to disable.
5. Change the boot order, so that the USB will be on top.
6. Save the changes and exit. Then shut down the computer.
7. connect the USB, turn on the laptop and press the F12 key straight away, this will bring you to the boot menu to select the USB.
* If you still unable to get to the boot menu, try oading the BISO again, go to the boot tab and Change the boot mode from UEFI option to Legacy.
You can see how to do it here: