Any AC will need an exhaust (the rear side of an Air Condistioner) to throw out hot air into open. So there are two parts to the question 1.

Where to fix the AC 2. How to make sure that the exhaust of AC has an access to open air. For 1, you either need to break the wall and get the AC fixed in the Wall or Chillwell 2.0 Preis alternatively, since there are no windows, you can reduce the height of the door and get the AC fixed above the Door.

For 2, you can get a duct stretched from the AC to open air and get an exhuast fan to pull the hot air from the AC.