To activate the product key on Steam, you first need to install the Steam client application. You can download this here.

After downloading and launching the application, follow these steps:

1. Log in using your Steam credentials and select “ADD GAME” as shown in the image below. You will receive 3 options, from which you need to select the option “Activate the product on Steam”.

2. After the product activation window appears, select Next.

3. Select the “I agree” option, because you need to agree on a Steam subscriber agreement to continue.

4. Copy the game key and paste it into the “Product Code” field, then click “Next”.

See which cards Steam Key Activation available for purchase now