Hi @Auseli,
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:
https://anabin.kmk.org/anabin.html
https://***.kmk.org/zab/statement-of-comparability.html
Here is an example of the process and documents needed in Berlin:
https://service.berlin.de/dienstleistung/329328/en/
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.
Best,
Éanna