I don't know how to cast anim instance

Hello everyone, I managed to fix my other trouble but not this one. I put sphere collisions on the left hand and on the right hand of my character. But, I don’t know how to play my anim montage and do damage at the same time. I have my damage system which works perfectly. My anim montage works perfectly. But I don’t understand anything about collisions. So here’s what I did trying to combine anim montage and applying damage. I actually managed to make it work but the collisions are interacting with my own character’s body and decreasing the health bar, which is not what I want. I want to decrease someone’s else’s health bar, not my own.