Custody/Child suppot

If i have full custody and I let my daughter live with her dad in another state and he wants custody does the law allow the father to waive all child support in NC?

I cannot advise about the laws of another state, but in North Carolina, a party cannot waive their right to child support. The support is for the benefit of the child and not for the parent. There are ways to get around through use of language in the agreement about how the child’s needs are addressed and how those do not require a direct payment of support at the time of the entry of the order. That does not stop someone from filing a motion to modify and requesting payment of child support later.