extraction question

[Sugamotomagazaki]

new player here, whenever i play the extraction mode we get annihilated by other players even right after we spawn. I;ve also noticed that emptying my whole clip one someone isn't enough to kill him while they just turn around /shoot me once and i'm dead which means they have better gear than me.
Am i doing something wrong here? i can't seem to achieve anything and it started to feel annoying.