Assuming you have an internet connection on this computer all you have to do is download and save the files in some convenient location then re-boot the computer.
One of the options when you see the boot screen - the one that probably has 'Fujitsu' all over it - is to 'flash' or upgrade your BIOS. Once yu start the process you will be asked where the file(s) are located, browse to that location and click 'run', 'install', 'update' or whatever it says. Once the update is done the computer will re-boot itself.
As I said above, make sure that this BIOS update is correct for your motherboard and chipset. Do that by checking the exact model number against their web-site.