[Very Confused] How do I damage an actor

I am very stuck as to how I would go about making my characters (this is a 1v1 arena style fps) hit each other with projectiles and inflect damage.
Plz respond if you can
Thx

In the projectile BP use the EventHit Node and from it use an Apply Damage Node you can use any of the damages such as radial or point. Something like this: