How do I get rounds to work on a wave-based game?

This did work, but then I changed what I had as a Player to a FirstPersonController, and then health, and rounds didn't work. I had help getting health done. But now the Player won't die, and the Rounds won't go to the next number.

using System.Collections.Generic; using UnityEngine; using UnityEngine.UI; using UnityEngine.SceneManagement;

public class Spawners { public GameObject go; public bool active; public Spawners(GameObject newGo, bool newBool) { go = newGo; active = newBool; } }

public class GameManager : MonoBehaviour { public GameObject panel; public delegate void RestartRounds(); public static event RestartRounds RoundComplete;

 private int health;
 private int roundsSurvived;
 private int currentRound;
 private PlayerDamage playerDamage;
 private Text panelText;

 public List<Spawners> spawner = new List<Spawners>();

 void Start()
 {
     Time.timeScale = 1;
     panel.SetActive(false);
     playerDamage = GameObject.FindGameObjectWithTag("Player").GetComponent<PlayerDamage>();
     panelText = panel.GetComponentInChildren<Text>();
     foreach (GameObject go in GameObject.FindObjectsOfType(typeof(GameObject)))
     {
         if (go.name.Contains("Spawner"))
         {
             spawner.Add(new Spawners(go, true));
         }
     }
 }

 void Update()
 {
     int total = 0;
     health = playerDamage.health;
     if (health > 0)
     {
         for (int i = spawner.Count - 1; i >= 0; i--)
         {
             if (spawner[i].go.GetComponent<Spawner>().spawnsDead)
             {
                 total++;
             }
         }
         if (total == spawner.Count && roundsSurvived == currentRound)
         {
             Debug.Log("Checking if executes");
             roundsSurvived++;
             panelText.text = string.Format("Round {0} Completed", roundsSurvived);
             panel.SetActive(true);
         }

         if (roundsSurvived != currentRound && Input.GetButton("Fire2"))
         {
             currentRound = roundsSurvived;
             RoundComplete();
             panel.SetActive(false);
         }
     }
     else
     {
         if (Input.GetButton("Fire2"))
         {
             Scene current = SceneManager.GetActiveScene();
             SceneManager.LoadScene(current.name);
         }
         else
         {
             panel.SetActive(true);
             panelText.text = string.Format("Survived {0} Rounds", roundsSurvived);
             Time.timeScale = 0;
         }
     }
 }

}

there is the code for the GameManager that controls the rounds, IDK what is different between the FirstPersonController, and the Player I had.