Getting player input for stealth takedowns/executions

Hey there. I’ve just started learning Unreal and I’m trying to make a stealth type gameplay blueprint. Only I’m basically a beginner and I’m having lots of issues here and there.

Basically what I’m trying to do is have a system where the player can sneak up behind an enemy, and when the former touches the box collision of the enemy it checks if he’s aware or not. Or if he is and is fighting you but has less than 20 health you can execute him.

For now the branches seem to work if I simply overlap. But, I’m trying to incorporate actually pressing a button to “activate” the kill.

Only what I’ve tried so far hasn’t worked. In fact, I even tried to have E with a print string to see if that works. And it didn’t. But it seemed to work on the world/level blueprint.

Also, the blueprint in the picture is the one on the enemy.

Hope I could get some pointers.