How do you Ground RB ffs

(WARNING: Intense Salt Incoming) I play Germany and I mainly play the Jagdpanther 38, the StuGs, and the Pz III. I have gotten all of these through Ground AB. I go into Ground RB games and I have no idea wtf to do. I try to sit back and look for tanks, and then I get one-shotted by a person I didn't even see, usually from an extremely long distance away. I'm not moving either. I know how to use binoculars and the sniper stuff but that doesn't fucking help. Wtf am I supposed to do, how do I not fucking get killed, and how do people get a ton of kills?