Is it leaking from the water pump or radiator? Is the system properly pressurized?
could be your thermostat or you have no antifreeze coolant or your water pump is going bad
20L of 50/50 mixture DEXCOOL plus water mixture
when you go through deep water
see answer given on how to change water pump on 92 deville. Same car.
where is water pump located
How to replace the belt
show location of 97deville water pump
a 50/50 mix of water and a good quality antifreeze
If a water pump is bad they usually leak coolant
Front of engine---r/s underhood
Get manual from the parts store or from AUTOBOOKSONLINE.COM