It is possible to change to a work permit. However, the work permit is for people with a qualification. You need to have your qualification recognised as comparable with a German one. This can be done using the database Anabin or the authority ZAB:
Here is an example of the process and documents needed in Berlin:
The process and documents, however, should be the same throughout Germany. Once your qualification has been recognised and you have an offer of a qualified position, you can apply to change your permit.