Draining coolant and water from P38

hello

i need to drain the water/antifreeze from the car. i dont know what is currently in it and i dont want to mix the antifreeze as ive heard it can mess things up. so just want to drain everything and put all new in.

just want to know is there any other drain plugs apart from the one under the radiator to drain the coolant/water ive heard there is another one but i dont know where anyone know?

also what is the best antifreeze to get for a 4.0 p38 or does it matter? thanks.

theres a rain plug somewhere on the engine block should show you where it is on rave