Sorry to tell. but you can not do an IFR flight in Germany on a German license if you do not have a BZF 1.
A BZF 1 is a radio license that certifies you that you are proficient in English radio communication.
You ere also not allowed to fly outside of German speaking territory if you do not have this type of radio license.
Further, there are a lot of company's that build aircraft in country's were English is not the native languish. There is Brasilia, Bombardier and Airbus Industry. All of them supply there aircraft manuals and updates in English. They offer other languishes but always state that the valid version is only the English version and English is the master document.
I´m German and had to learn English to work in civil aviation and I believe that if you want to have a chance to have a career in aviation you will have to learn English!
Try the postal service if you are french.
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