Can you immigrate to Germany after CCIE is passed, as a skilled immigrant?

You can't. Germany is not an immigrant country, so almost only those who have worked here for five years can obtain permanent residency. If parents can only visit relatives in Germany as relatives, they can stay for three months at a time, even if the child gets German citizenship. And unlike North America or Australia, the German visa for visiting relatives cannot be extended here. If you want to stay in Germany, you can only go back and apply again.