Collide with worm deduct BP and kill the worm

Basically i will have an worm prefab walking around the scene. So if the player collide with the worm, it will have deduct on their's BP. As i need the enemy prefab to be walking around the scene once started, i create an animation for the worm and check the 'IsTrigger'. So if the player collide with the worm, it will lose its BP. But i don't understand why there is no effect (mean no deduction of the BP).

Next, i want the player to be able to kill the worm, like "stepping" on them and the enemy prefab will be destroy. Quite similar to the super mario game. How can i do it?? thank you.

 if(hit.gameObject.tag == "worm")
     {
         HealthControl.LIVES -= 1;
         print(HealthControl.LIVES);
         // play a sound clip at the exact position we hit the object
         AudioSource.PlayClipAtPoint(hitSound, transform.position);
     }