How does Propkill Help work?

I installed a new Garrys Mod hack, HackBETA, a Remake from AHack. I want to Propkill someone, but the prop flys, without killing someone randomly, how can i set that the prop flys on a enemy?

with the power of the gods you can do anything you want
all you need to do is believe in yourself
but knowing Lua will probably be the biggest help

I cant understand