Heavy Fire: Afghanistan is a super fast playing on-rails shooter set in modern-day Afghanistan featuring tanks, assault vehicles and helicopters. The game offers 60 awards, one machine co-op for up to four, Steam Cloud, Leaderboards and Trading Cards.
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