My Camera won't activate trough script

Hello Unity Users. I'm trying to make an simple Multiplayer FPS and i want to activated my Camera trough script... I've made one script but this does not work.

 using UnityEngine;
 using System.Collections;
 
 public class NetworkManager : MonoBehaviour {
     
     
     void Start () {
         Connect();
     }
     
     void Connect() {
         PhotonNetwork.ConnectUsingSettings( "Project LuPaLu v001" );
     }
     
     void OnGUI() {
         GUILayout.Label( PhotonNetwork.connectionStateDetailed.ToString() );
     }
     
     void OnJoinedLobby() {
         PhotonNetwork.JoinRandomRoom();
     }
     
     void OnPhotonRandomJoinFailed() {
         PhotonNetwork.CreateRoom( null );
     }
     
     void OnJoinedRoom() {
         Debug.Log("Room Joined");
         SpawnPlayer();
     }
     
     void SpawnPlayer() {
         GameObject myPlayerGO = (GameObject)PhotonNetwork.Instantiate("PlayerController 1", Vector3.zero, Quaternion.identity, 0);
         Debug.Log(myPlayerGO);
         ((MonoBehaviour)myPlayerGO.GetComponent("PlayerMovement")).enabled = true;
         ((MonoBehaviour)myPlayerGO.GetComponent("MouseLook")).enabled = true;
         myPlayerGO.transform.FindChild("Main Camera").gameObject.SetActive(true);
     }
     
 }

Thanks for your Help.