in the US there is no minimum age - you might be confused with adoption law minimum desired age of notice.
Notify him.
not if you're the father.
Yes both parents still have a legal obligation to support the child monetarily.
Visitation is not based on any particular age.
When they can say it.
If you mean, child support that was ordered but not paid - yes.
at age 18 because that child is considered an adult.
He will not be granted legal custody.
Not enough info given in order to answer. What is the court case? What is the age of the "child?" Is the father an attorney?
If the child is a beneficiary, and depending on the amount, the state will appoint a trustee to oversee the funds in the child's interest until they reach legal age. Legal age for this purpose varies by state.
Same as before. Having a child wont change that and it will still be statutory rape if she is below age of consent and he is 18+. Even if he is the father of the first child.
There is no legal age