thank you for sharing your question with the Wefugees Community.
After finishing your Ausbildung, if you find a Job, which matches your qualification, for example, your current employer hires you, you can immediately apply for a residence permit based on section 19d of the Residence Act of Germany at your respective Foreigners Office and you will get it. You will have this residence permit for two years, and you have to work in this field of your Ausbildung for two years.
After the 2 years of work in this field, in which you have done your Ausbildung, you will be free to work in any other fields.
That is why, it is called 3+2 (3 years of Ausbildung and 2 years of working in this field and after that you are free to work in other fields).
I hope, you have got your answer. I am a MBEON consultant. If you wish to contact me directly, you can see my profile and follow the instructions there.
Best wishes
Fardeen Noori