Please note that it is your responsibility as a student to obtain the required visa. If you are admitted, we will send you an admission letter with which you can apply the nearest German embassy/consulate. If necessary, we can also write letters of support and be available for questions directly by the embassy but we cannot influence visa proceedings.
Visa proceedings can take several months so we strongly advise you to apply early to the degree programme (see here for the possibilities of early decisions) and to apply for your visa immediately after getting admitted. An overview of relevant steps to obtaining a visa can, for example, be found at the website of the DAAD (German Academic Exchange Service).