Did Hitler himself ever kill anyone?
No, there is absolutely no solid evidence to suggest that Hitler personally killed anyone. Although he served as a soldier in the First World War, he was posted as messenger between camp headquarters and the frontlines, which meant he would not have directly been involved in any combat and had no recorded kills at the end of the war.
There is wild speculation that Hitler may have killed his niece, Geli Raubal, who he supposedly was having a secret affair with, but the evidence surrounding the event is extremely circumstantial and it is impossible to say whether he was complicit in her death or not.
In short, there are no documented cases of Hitler ever killing anyone