I would suspect a busted hose or radiator. Should be very easy to find the source of the leak.
heat core. leak. thermostat. no antifreeze.
If it's coming from lower front I'd say water pump
If it is motor oil in the anti freeze, then it is either a cracked head, cracked engine block, or a head gasket blown. If it is transmission fluid in your antifreeze, then the radiator is leaking from the transmission cooler ----- although usually that would cause antifreeze to be in your transmission fluid.
Intake manifold gaskets are leaking, intake manifold is warped.
Cracked head or a blown head gasket. good luck.
If you drive with no antifreeze in your radiator you could ruin the motor. At a minimum you would probably blow a head gasket. The worse thing that can happen is that the motor will freeze up.
It could be that the window motor has stopped working.
If it comes from the side of the motor and not from another source such a a leaing hose, then it is almost deffinatly a leaking head gasket. not a cheap or easy fix.
antifreeze keeps your car from overheating, it flows thru your radiator hose, without it your motor would blow
A 1992 Mercury Grand Marquis would have come from the factory with a 50 / 50 mix of distilled water and GREEN color antifreeze ( meeting Ford specification ESE-M97B44-A )
That depends entirely on which motor and It's coolant capacity. An average would be about 2.5 gallons
the most common cause would be a stuck closed thermostat.