You are in a bare room.
There is one table at the end with a key on it.
That key opens the locked door that you are standing against.
You simply have to walk across the room, obtain the key and walk back again to unlock the door.
Oh, and be careful of the five lasers that are distributed across the room. They are invisible, security lasers. They could be high up, low down, or just in the middle. They could be vertical, horizontal or diagonal.
If you happen to touch one, spikes that are a good few feet long emerge from the walls, cieling and ground, tearing you apart for sure.
Good Luck!