In TransOcean 2: Rivals you face a new challenge as the boss of your own shipping line in both single-player and - for the first time - multiplayer mode: The international competition has gotten a lot tougher and the battle for the most lucrative contracts has only just begun.
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