Unexpected Symbol and Parsing Errors

Im making a player health and death script and their are 2 annoying errors that when I try to fix , they add more errors. Can please some one help (C# syntax only).

Errors:

Assets/Scripts/PlayerHealthAndDeath.cs(12,17): error CS1525: Unexpected symbol `{' Assets/Scripts/PlayerHealthAndDeath.cs(18,10): error CS8025: Parsing error

 using UnityEngine;
 using System.Collections;
 
 public class PlayerHealthAndDeath : MonoBehaviour 
 {
     public float playerHealth = 100f;
     public float damage = 10f;
 
     void OnTriggerEnter(Collider other)
     {
         if(gameObject.tag = ("Enemy") // Symbole error
         {
             playerHealth -= damage * Time.deltaTime;
         }
     
     }
 
     if(playerHealth == 0) // Parsing error
     {
         Destroy(this.gameObject);
     }
     
     
 
 }