Custody in NJ is divided into two parts - legal custody and residential custody.
The VAST majority of cases are "joint legal custody." This means that either parent can authorize medical treatment, access records, etc - both parties are equal for all legal purposes.
Residential custody is where the child lives. It can be either shared custody (much more common these days) on some kind of rotating schedule, or one parent can be the Parent of Primary Residence (PPR) and the other the Parent of Alternate Residence (PAR).
You can go to the court (Freehold for Monmouth County) and ask for "Family Part Intake" or "Family Part Filing Unit" - they'll have forms you need to fill out for custody, parenting time, and support. You'll get a computer generated notice for a hearing about a month later, where the judge will decide the issues. If there's any conflict over custody / parenting time, you will be referred to court mediation before the judge calls it.
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