Dear @Chappy,
Welcome to the Wefugees Community and congratulations on your new family member :-)
As father of a German child you may want to apply for a residence permit according to section 28 of the German Residence Act.
Please see this thread for a detailed explanation on the application process including a list of required documents.
I hope this helps and don't hesitate to get back to us with any further questions.
All the best for you and your family,
Meike