So yes, in that NJ Transit operates* trains and busses throughout the state.

The transit routes are more or less designed around commuting to metropolitan area centers. What that means in practice is that for most of NJ, transit is oriented towards commuting to NYC or Philadelphia, as opposed to being able to get around town with reliable frequencies. So if you work in NYC, Philly, or Newark, you might not need a car to get there. When you start talking about getting around your immediate area, you'll probably need a car unless you're in one of NJ's cities. Even then, mass transit coverage isn't that good or reliable when your destination remain within the state.

* NJ Transit is also kind of a franchise with various operations being run by private companies contracted with the state. This sometimes becomes a point of conflict with the buses, with the private operators want to reduce frequency.