^^^Not to interrupt anything here, but if you venture into a pvp-enabled zone then there's nothing stopping other players from killing you, unless you're in a gang with another player or group of players in which case they can't attack you but other players still can. I'd recommend doing what Lava said and don't generally go into pvp-enabled zone if you don't want to be attacked and killed constantly (some good armour and a good weapon would help you fight back too)
Also for a tp kill/attempt to kill, you can make a “player report” with screenshots if that happens. You can also contact an online police officer.