How do Games activated by an activation key work?
After the payment is approved, an activation key will be available in your Nuuvem account, wich is a code that will give you access to your game. Access your Nuuvem account, click on the game you purchased to display the activation key. This code that is displayed is what will give you access to your game or DLC. Firts, It must be inserted in the respective game activation platform (Steam, Ubisoft Connect, Batlle.Net etc) before you can download your game.
Each key can be activated once, on a single account.
Below is an example of where to find your activation key in your Nuuvem account: