Low coolant on 2002 Dodge Caravan

I replace my radiator. And the thermostat. At firts when I did the radiator . I drove it and it overheated right at the I went and replace the thermostat.and no over heat or nothing.but I been putting antifrezze and it gows doesnt go all the way empty just on the low line.? I dnt kno what seems to be the problem

Asked by for the 2002 Dodge Caravan
look for a coolant leak while under pressure