Entry Regulations for Germany
Before entering Germany please contact the German embassy in your home country (or the country from which you plan to travel to Germany) for information about entry and residence.
It is extremely important to apply for a student visa in good time. The application procedure can take several weeks.
If you have not been accepted already by the TUHH or by a "Studienkolleg" you can apply for a student applicant visa (necessary documents: 1. a qualification for admission to higher education, 2. proof of financial resources, 3. an acknowledgement from the TUHH confirming the receipt of a complete application). This visa is valid for three months. That gives you time to contact the universities directly. Within this period you must gain admission to a study program.
NEVER ENTER GERMANY WITH A TOURIST VISA!
Foreigners registration offices cannot change it into a student residence permit. The student residence permit as a matter of principle only entitles you to study and does not allow you to take up employment.