Hey Ujjwal Rana,

Studying in Germany is not free at all. Somehow few of the universities make it for free but for few of them you need to pay the fee and your living expenses too for both type of universities. Anyways you can find all your doubts in the given link.

https://www.topuniversities.com/where-to-study/europe/germany/study-germany-frequently-asked-questions#Can-I-study-in-Germany-free-of-charge