Welcome to the Wefugees Community and thank you for reaching out to us.
On the electronic residence permit cards, which are usually issued in Germany in these days, you can read either "Beschäftigung gestattet", "Erwerbstätigkeit gestattet" or "Siehe Zusatzblatt". As the cards don't provide enough space to explain all the conditions which apply with certain residence permits, the immigration offices hand out an additional green paper - the "Zusatzblatt" - explaining them. Therefore, it is not the "Zusatzblatt" which restricts you regarding work/employment in Germany, it is the residence permit. If there are any possibilities to change your type of residence permit, is depending on many factors.
I would recommend you to contact a migration counselling office to discuss your individual situation and your options. I will also link our dear expert @mbeon-Christine here, maybe she can give some advice already or add information.
In any case, please don't hesitate to get back to us with any further questions.
All the best,