WHERE DO I GO WITH THE KEYCARD
Take the keycard to the door across from the reception area that you start in. There's a little scanner. When you interact with the scanner, it'll beep for a few seconds. Stay near it until you hear a click. Then you can open the door.
If you need any extra help, Bis35 posted a playthrough in the comments, and they go through the whole thing.
Thanks for playing :)