1993 Nissan Maxima Hill Car Maid Squill Noise Started Roll Backwards Wood Stop

i was going up a hill an my. car maid a squill noise an then started to roll backwards an wood not stop unless i hold brake.once i let it roll down the hill i then tryed to put it in park an it maid the noise again and wood not park it just kept rolling back and wood not go in any gear. its like its in neutral an wont go into gear if any one know what happen please help