the car is leaking antifreeze and the engine just came on a new radiator was put

Hello, The cooling system is a sealed system which is under pressure in an engine which is warmer than ambient temperature. When there is a leak, it is impossible to build the right amount of pressure, so the engine overheats. When a leak is fixed, the pressure is back on, so if any seals were damaged when the engine was too hot, they are now more likely to fail. If the radiator or radiator hoses are leaking, the radiator is either defective, or improperly installed. The check engine light alerts you to stored trouble codes, have it scanned and let me know what code you get back.