OK. I'll help you on this but first there're a couple of things you need to be sure yourself. First, be 100 % sure, this is the right update for your motherboard, and you have not accidentally selected the wrong one. Check and double check.
Second, see if you can find a description somewhere about the changelog for this bios- so you know whether you get any benefits from the the flash. Of course, some peoplw will update bios no matter what but it makes more sense if you get some benefit.
Then come back and I'll guide you on how to go about it.