How much notice in nj do i need to get my step daughter to move out of our house? She pays nothing to live here and we support her n her 3 yr old daug

Even relatives need court orders in order to force a person to leave absent their consent. Since your step daughter is probably not a paying tenant you would have to file what is called an ejectment petition which is for non tenant occupants. I am presuming your step daughter is over the age of 18.