My Radiator is Average Heating Up?

I Have to Put Coolant @ 1st, then after a Long Simple Drive About 3-5 Miles distance driving it on a 35 MPH Zone. I had to refill water in the reservoir container. It's like where did I put the coolant & it's Gone? I hear a gurgling from the upper hose like its having a hard time drinking the water? Where & How may solve this problem with your assistance? Thank you awaiting for your reply/response.

P.S.
I Already change the water pump & thermostat components.