How to make a Glory Kill/TakeDown System?

Hello, I am trying to make a takedown system. I have already made the animations in Moon Animator (They are first person by the way.) And I have exported both the Player and Enemy animations to roblox. But I want to know how I would go about doing this: When you are close enough to the enemy, you can press the button F on your keyboard and it triggers the takedown animations. and after the animation is over, the enemys health drops to zero. If anyone could help, it would be appreciated, thanks :D

(if you dunno what im still going for heres a vid:https://www.youtube.com/watch?v=1RYgSTavtP4)