Accommodation

Finding a place to rent in Germany can be difficult - depending on the location, with Western cities the worst, Eastern countryside the easiest.
But in any case it is never short-term!
You typically need a few weeks to find a place (in the location you want, with the amenities you like and for the price you can pay), plus there is typically a period of 1 - 3 months between signing the contract and your actual move-in, because places are advertised (and quickly taken up) before the previous tenant moves out.
Since you are coming next week already, I can only recommend you book short-term accommodation (e.g. a hotel, hostel or serviced apartment) for the initial time, until you have a permanent place to stay.
Good luck!