Sea of Stars is a starship roguelike, a sandbox adventure game of interstellar exploration and combat. Travel from star to star, upgrade your ship with new systems and weapons, build up your flotilla with allies and mercenaries, and take on a variety of alien menaces.
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