At the very beginning of Control you discover a Clearance Level 01 locked door. This guide will tell you How To Unlock Clearance Level 01 Door In Control so you can enter the restricted area and loot the mods and other rewards once inside.
Your Clearance Level is a security measure tied to you throughout the entirety of Control. Open your menu and check the Assets tab. Here you will see a number of details, one of which is your Clearance Level. Once you reach a specific Clearance Level you can access all areas of that particular security level, it is not a one-time use access card.
How To Unlock Clearance Level 01 Door In ControlYou are unable to unlock the first Clearance Level 01 door you encounter for some time. You need to progress through the main story until near the end of the second mission. You are tasked with finding the Hotline. It’s part of the main story, you cannot miss the first clearance level.
Once you have progressed far enough to unlock it, simply return and open the door.