Watch Persian Lessons (2020) online

Lessons of Persian, a film directed by Vadim Perelman, is set in France in 1942, a country occupied by the Nazi threat, and tells the story of Gilles (Nahuel Pérez Biscayart). During an SS raid, the man is captured along with other Jews and imprisoned in a German concentration camp.
When asked if he is Jewish, Gilles lies saying that he is Persian, thus escaping a certain end, but on one condition: teaching Farsi - a language he does not know at all - to the camp director Koch (Lars Eidinger); in fact, once the war is over, the Nazi commander dreams of being able to open a restaurant in Iran. This is how to survive Gilles is forced to invent a language made of meaningless words and sounds, hoping not to be discovered.