Easiest way to shoot, and kill an enemy?

Unity Engine
, ,
1 
public class SpawnBullet : MonoBehaviour
{
    public GameObject prefabBullett;
    public Transform centerBullett; // empty gameObject

    GameManager _gameManager;

    void Start()
    {
        _gameManager = FindObjectOfType<GameManager>();
    }
    void Update()
    {
        if (Input.GetKeyDown(KeyCode.Space))
        {
            GameObject bullett= Instantiate(prefabBullett, centerBullett.position, centerBullett.rotation);
            Rigidbody rb = bullett.GetComponent<Rigidbody>();
      
      rb.AddForce(centerBullett.forward*10,ForceMode.Impulse);

            Destroy (bullett,2);
        }
    }
}

private void OnCollisionEnter(Collision collision)
    {
        if (collision.gameObject.tag == "Bullett")
        {
            Destroy(gameObject);      //delete yourself
            Destroy(collision.gameObject);
        }
    }