Some students think, that they might need some knowledge of German before they can start their German course in Germany.
It is definitely a recommendation to learn as much German as you can, before you come to Germany, but it is not mandatory. A lot of international students start from absolutely or almost zero.
If you really have zero or almost zero knowledge of German you’ll definitely have to expect that learning German will be a full time job for you, as intensive German courses for students in Germany advance very quickly.
But there is no special level of German required before you start. So the only requirements for your German course in Germany are that you have enough money to pay for the course and the cost of living and that you’ll get a language course visa.
About these topics I have written here: