Hi @MHageb
You currently have a permit under section 16b. You can change to a permit under section 16a to do a course to obtain a professional qualification. Such a course is either in the form of an Ausbildung or Weiterbildung.
Training to be a pilot is what is called a school-based Ausbildung (schulische Ausbildung). If the course that you wish to do will lead to a professional qualification that is recognised in Germany, then you can change your permit to 16a.
Best,
Éanna