I was trying to buy a game I already redeemed my apple gift card how do I use it to buy the game
Im trying to buy a game in the App Store I already redeemed my apple I tunes card how to I use it
Just find the game in the App Store, and click the price button. The purchase will be automatically charged from the gift card credit balance on your account.
You do not need to do anything special.
See here: How iTunes Store purchases are billed - Apple Support