Welcome to the Wefugees Community and thank you for reaching out to us.
I saw that you opened another thread about the same question (Can I apply for an Ausbildung with a language visa?). In order to keep a better overview and information in one place, I closed that one. I hope this is okay for you.
Do I understand correctly, that you are holding a residence permit according to section 16f (residence permit for attending a language course) of the German Residence Act and you want to change it to a residence permit according to 16a for making an "Ausbildung" (apprenticeship/vocational training)?
According to this table (compiled and published by the GGUA), you can apply for a respective residence permit if you finished your language course sucessfully. If you quit it, the residence permit for vocational training may only be issued in more exceptional cases. Please follow the above provided link for a list of the requirements in detail.
I will also link our dear @mbeon-Christine here. Am I right on this and can you maybe give some more information on this topic?
I hope this helps and please don't hesitate to get back to us if I did't get your situation or if you have any further questions.
All the best,