MY HEATING COIL WENT OUT ON MY CAR. THERE IS WATER LEAKING INSIDE THE CAR ON THE DRIVER SIDE. ALSO MY RADIATOR IS ALSO LEAKING. WHICH ONE IS THE MOST IMPORTANT ONE TO FIX FIRST. DUE TO MY FINANCES I CAN ONLY DO ONE AT A TIME.
Both are in the same system, fixing one is not going to work.
I would suggest fixing the radiator first. Test and ensure that it is the heater core that is leaking and the water is not from other sources. Once it is confirmed, that the heater core is leaking, disconnect the heater core hoses and plug them to disable the heater for the time being.