Obtaining a Visa and a residence permit to study or to find a job in Germany, is based on certain factors such as which country you belong to, what is your purpose of coming to Germany or for how much time is a foreign student planning to stay in Germany. It would be helpful if you decide on these questions and get the paper work done in advance before applying for admissions in a German University.
There are different set of rules for the nationals of different countries who intend to study in a German university. Like, the nationals of European Union, Switzerland, Norway or Liechtenstein need only an identity proof to stay in Germany, it is not mandatory for them to have visa and other formalities like other foreigners who have to obtain a visa if they want to stay for more than 90 days. For some countries' nationals, like Australia, Israel, Canada, New Zealand, USA, Japan, South Korea, they have the luxury of applying for visa even after arriving in Germany and for other than these country’s national it is necessary to apply before arriving.
For different countries, there are different rules. If you are from Venezuela, Uruguay, Paraguay, Nicaragua, Mexico, Malaysia, Croatia, Chile, Brazil and Argentina, you can stay for less than 90 days even without a visa. For more information you can reach out to the foreign affairs office or the German embassy. There are different kinds of visas which depend upon the purpose of applicant's visit to Germany. If you have secured a seat in a course of a German university you have to apply for the visa to stay into the country during the course time of your study. If your candidature is not confirmed for a university, then you can apply for the visa to visit the University for Admission Purpose or to write a test for admission.
It is mandatory for a student to get a German health insurance and also, a proof of financing to study in Germany is required. After getting a visa for the first three months by confirming admission into a university, you have to apply again for the residence permit for remaining time of stay in the country which can be done with help of a counselor at the consulate office of your country in Germany. You have to register yourself for confirming your residence in Germany at the foreign affairs office.
Thus, it can be concluded by saying, all you need to stay in Germany for the studies is health insurance, registration confirmation, enrollment letter, identity proof and last but not least the visa. This visa offered, is valid for only two years. If you intend to stay further you need to obtain permission for the same. To conclude these formalities it may take a while to be completed so if you are planning to study in Germany, you need to start planning to get these formalities done early and take professional help in applying for them, so that your stay is well planned and a relaxed one in Germany.