Visas can currently only be issued if the intended entry is absolutely necessary. The exceptional cases permitted entry into Germany are explained in both English and German on the website of the Federal Ministry of the Interior, for Building and Home Affairs under “Coronavirus: Questions and Answers” and there under “Travel restrictions / border controls”: https://www.bmi.bund.de/SharedDocs/faqs/EN/topics/civil-protection/coronavirus/coronavirus-faqs.html
Zimbabwean or non-EU nationals need a visa in order to enter Germany.
The type of visa you require depends on how long you plan to stay. Are you planning a short visit to Germany, e.g. for a holiday? Or would you like to stay longer, e.g. to attend university?
Please choose how long you are planning to stay.