i’ve come across so many razes who only buy shotguns and they all die at the beginning of every round going double negative by the time the game is over is this not considered throwing?

Is my crosshair accurate? I'm new, bad at aiming and want to be sure it's 100% a skill issue. As you can see at the end, some I get right and others I blow it when it's right in front of me. I want to make sure I'm practicing the right way...