Most DMG but can not secure kills....what

Actually, I have been getting killed not with one clip, but one shot, or even one punch even with purple armor.  This game is not just difficult, it is impossible unless you are one of the people with games that can do that. The last person that killed me was not with a team, he was a solo no fill like I was.  I wish the game were like it was supposed to be because I can imagine a gun fight would be fun, being able to hit people then hide behind an obstacle, then hit people again and use strategy.  Sadly, that is impossible to do.  I have tried everything and after I learned tonight there is no way to level up it just takes the reason to play out of it.