Welcome to Wefugees and thank you for your question.
Unfortunately, you cannot get married with a Schengen tourist visa in Germany. There is a specific visa type for people who intend to travel to Germany to get married: https://www.berlin.de/labo/willkommen-in-berlin/einreise/visumsverfahren/artikel.600163.en.php
If you are interested in getting married in Germany, please have a look at our Blog article with a detailed description in German and English: https://wefugees.wordpress.com/2018/04/20/heiraten-in-deutschland-how-to-marry/
You can also try and browse our platform for previous cases! Simply use our search bar on the right side and type in words like "marriage germany" / "getting married", etc.
Feel free to reach out to us again if you have any more questions.
All the best,