Men of War: Assault Squad 2 - Airborne is the second DLC for AS2. It comes with a set of new features and additional singleplayer content. Fight as airborne commander behind enemy lines and support allied landing operations. The success of these operations will depend solely on you!
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