I am new in Berlin

Can someone recommend a good German teaching institute at least to level C1-C2 ?

In general, the Volkshochschule (which exists in all major towns) is a good address for value-for-money German classes, as are other non-profit organisations and sometimes universities, which you can find by Google.
Commercial language schools, which charge more but might offer better quality and one-on-one lessons, often advertise in stations and places where foreigners congregate.
If you find a good one in your city, you are welcome to post the details here!