Slip into the role of Daniel Hanson, commander of the first mission to a remote planet called Meridian. Assured of the fact that the planet is uninhabited, the unexpected reception of a distress call from the surface could mean many things, none of which you are prepared for.
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