Final Rush is an intense, difficult, co-op multiplayer FPS, where the players fight against waves of hundreds of robotic enemies. Destroy robots to earn experience points which can be used to rank up your player; improving skill, customizing armor, and upgrading weapons.
Open the Steam client, login and locate the Games tab on the top menu. Click this and then select “Activate a Product on Steam…”
Enter your unique code that's displayed on the 'Orders' page of CDKeys.com and follow the prompts to activate.
Your game is now viewable in the “Library” tab and is available to download/install when you’re ready. You can find additional support for the Steam client here: https://help.steampowered.com/en/wizard/HelpWithSteam