Who has rights to the child in this scenario?

Your boyfriend has no rights to the child. Bio dad has rights regardless of what the birth certificate says.

Child Support?

Fair or not, that's how it's done. The stepparent doesn't have a legal obligation to support the child.

Can I get a free divorce? If he's in prison

It's easy, but it's not free. You can file the documents yourself but you're still going to pay nearly $300 in filing and service fees. It's...

Do I need to call the attorney general's office and let them know that my 17 year daughter is now living with me

You need to file a motion to modify child support based upon the new arrangement.

Do I have to give my nephew back to my brother?

You need to file a complaint for custody ASAP.

I’m 25, can I file for back pay on child support?

No, you are not eligible to receive child support. Even if he did owe support it would be payable to your mom, not you.

How do you change a minors last name with a custody agreement in place?

If the child lives in NC, he cannot change the last name without mom's consent unless mom abandons the child.

Can the father of my child take her away from me and me not be able to do anything about it if I give her his last name?

The last name is irrelevant. Bio dad will always have custodial/visitation rights with the child.

Yes, they can make him do everything you mentioned. You should comply with all of their requests. If you refuse, they will think you're hiding...

Every paper has different pricing for this. You'll need to call and ask.