Dear @Jelena,
Welcome to the Wefugees Community and thank you for your question.
I am afraid that I haven't understood the context yet. Maybe you can provide a little more information, this could help us to give more tailored information here. Are you referring to the "Zusatzblatt" which is issued with a residence permit?
In general, a "Beifahrer" is indeed not the same as a "Kraftfahrer". As I read, to work as Beifahrer (usually responsible for loading instead of driving the vehicle) there is no vocational training needed. In order to work as a Kraftfahrer, however, you usually have to complete a three-year training course. Depending on your situation, it might be important to prove that he is actually working in a qualified job.
Looking forward to your response and all the best,
Meike