You pressed the F2 key at the wrong time. Ensure the device is turned off and not in sleep or hibernate mode. After that, press and hold the power button for five seconds, then release. The power button menu should follow this; press F2 to enter BIOS setup. If, after doing this, you’re still unable to access BIOS, the issue is likely your keyboard or the lack of keyboard drivers before the computer reboots. You can try another keyboard or port to determine the cause.