Anyone has an idea on how to use an Amazon gift card?

It happens that I participated in a contest by HUAWEI device a few weeks ago. The results were released this morning and I missed out slightly by being a runner up. The reward being a $77 USD Amazon gift card. Now I don't have much knowledge on it's usage although I know it can be used to purchase things at Amazon. I have tried doing some research but the information am getting is not leading me anywhere. So I just want to ask if anyone here has an idea concerning this Gift card thing.

As far as I know, a gift card can be used to purchase items on Amazon. There are options upon checkout to use your gift card. The among is then deducted from the card. It's just like using your VISA card for purchases.

I appreciate your help. I will try it out on their site when am ready and see how it goes. I believe I can manage a way through when the time comes. For now I will continue finding more information concerning it.