In New York, it is legal for a child to move out of his parent's home at the age of majority, which is 18. At that age and under normal circumstances, a person is judged to be responsible to make adult decisions about his living arrangements.
"Age of majority" is a legal term that indicates that a person is responsible for the majority of his actions. Conversely, a minor person is only responsible for a minority of his actions. Of course, circumstances often arise in which it is necessary for a minor person to be removed from his parent's home. In those cases, the decision of where the minor child must reside is left to an adult guardian or a court.