You generally access the BIOS screen by pressing the appropriate key while your computer boots—it’s often displayed on the screen during the boot process and will be noted in your motherboard or PC’s manual. The process for entering a UEFI setup screen can be a bit different.There are also more traditional DOS-based BIOS-flashing tools.The BIOS version number is displayed on the System Summary pane. Different motherboards use different utilities and procedures, so there’s no one-size-fits-all set of instructions here.
If you can't access your BIOS, your best course of action is to take the computer into a tech department instead of doing it yourself.
First, head to the motherboard manufacturer’s website and find the Downloads or Support page for your specific model of motherboard.
You should see a list of available BIOS versions, along with any changes/bug fixes in each and the dates they were released. You’ll probably want to grab the newest BIOS version—unless you have a specific need for an older one.
You copy the BIOS file to a USB drive, reboot your computer, and then enter the BIOS or UEFI screen.
From there, you choose the BIOS-updating option, select the BIOS file you placed on the USB drive, and the BIOS updates to the new version.