Given the prevailing Covid situation, the DAAD is offering online appointments. So even if you are not in Chennai, you can book an appointment with Team DAAD at the Information Point Chennai.
Please check your spam/junk folder for the confirmation mail. You will also get the link for the appointment in it.
Do read the basic information and check the databases mentioned on the appropriate webpages (https://www.daad.in/en/study-research-in-germany/studying-in-germany/). This will ensure that the appointments guide you further on your path.