Yes, holding your breath is necessary for a long shot as long as you don't hold it too long. That comes with your first shooting lesson.
I’ve had plenty of real range time in my life: Learned to shoot in the boy scouts in the late 70s, qualified expert marksman several times while in the USAF in the early 80’s, have hunted deer in NH with a winchester model 94 open sights, and hunted moose in Alaska with a scoped .30-06 Sako. I’m a better shot in real life than I am in the world of PUBG, but I aint terrible in the game either.
Oh and I do enjoy shooting targets at the range & did shoot one moose from 100 yards, but most times I ended up helping someone else pack one out. Sadly I sold all my guns(only 3: Sako .30-06, Winchester 94, Remington 700 pump) when I moved from AK to FLA. Thinking about re arming at some point.
“holding your breath is necessary for a long shot”
I think I was taught to take a breath, release it, and then act. It’s been a long time.