I got a leak everything full but i took radiator cap off after it cool down open lid it startied pouring out

It sounds like from your statement you are opening the reservoir and coolant is coming out. This is different than a vehicle cooling system leak. The system is typically under pressure, even for quite some time after the engine has stopped. If you are seeing a leak while the vehicle operates, then yes -- a pressure tester would be a great tool to use to find the leak. If you are saying the coolant comes out when you open the reservoir, that may be normal, depending on how long the vehicle has been sitting.