Depends on your Gameplay.
Just some quick example.
lets say you fire with a gun at your enemy.
on your player
you do a line trace, if it hits you use “apply damage” with X Damage you your enemy.
on the enemy, you use the event “on damage” where you could take the applied damage and subtract it from a health variable and check if the health is 0 or lower than 0 and if its true you call “destroy actor”
