Under New York State law, both parents must financially support their child until the child turns 21 years old. Child support also includes providing health insurance coverage until the child turns 21 years old.
If the child is under 21 and married, self-supporting, or in the military then the child is emancipated and the parents don't have to support the child.
In general, the custodial parent can get child support from the other parent, the non-custodial parent. The custodial parent is the parent who has physical custody of the child. This means that the child lives with this parent most of the time.
If the child is in foster care then both parents have a responsibility of paying child support.
If you don't have a child support order, you can file a support petition in Family Court. Or, you can go to your local Child Support Enforcement Unit to help you start the Family Court case.
If you have a child support order and want to change or enforce it, you can use the free and easy Support Modification and Enforcement/Violation DIY Form program. This program can ask the Family Court to modify the order. It can also ask the Family Court to enforce the order if the other parent is not following it.