Buy $15 Google Play gift card to purchase anything from Google Play Store such as Games, Apps, In-App Purchases, ebooks and more.
Your Google Account must be USA Region. If your account is not in USA region then you must use VPN when redeeming the code the first them. While VPN is ON and connected to USA server, follow the steps below. Once done it will as for USA Zip Code. Place a random US Zip Code (Search Google). Once successfully redeemed and account region is changed you can redeem codes without VPN.