I am non-EU resident doing a paid internship (Praktikum) in software engineering in Germany. I have received an offer from an outside company to work on a project for some hours on my spare time. Thus, I am wondering if I am allowed to do so in Germany considering that I have a Residence Permit (+ health insurance and tax number etc.) due to my full-time internship (40 hours per week) at the company.
I was told to either ask at the Finanzamt or Gewerbeamt but I would really like to know if there is even a way to do this legally.
If anyone was in a similar situation (is in Germany for a reason + wants to do part time freelancing) I would really appreciate the input.