Driver License (Cologne)

Hi All, I have a non-EU driver's license and an International Driver's license also (I have to sit fresh for a brand new German License). I have two questions Protected content long will I be able to drive with an international driver license before getting the German one? Protected content I be able to find insurance If i am purchasing a car with an International License?

thanks a lot, Garen

(ps looking forward to moving to Cologne.....)