If you need to ask, you should not update the bios.
A failed update can render your motherboard useless.
If you have a problem that is seriously hurting, and if there is a update that fixes the problem, only then should you update.
There are different methods, but I do not recommend using a windows based update procedure. Too many things can go wrong.
You should be able to download the new bios to a fat32 formatted usb stick.
You then use that to do the update.