How can I be put pon my child's birth certificate?

Be present when they are born and be put on.

File in court, with mothers permission to be added to birth certificate

Get court ruling to be added againt mothers wishes.

In general assuming the child is born and you are not on it, you are going to need an attorney

We really need more info to go on. Is anyone on the birth certificate now? In what state was the child born. How old is the child? Has a birth certificate been issued?