Pause Menu System

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


public class MenuController : MonoBehaviour
{
    public AudioMixer mixer;

    public bool inRegMenu = false;
    public bool paused = false;
    public GameObject playerCam;
    public GameObject uiStuff;
    public GameObject pauseMenuObj;
    //public AudioListener listener;

    public GameObject firstSettings;
    public bool settingsOpen;
    public GameObject settingsMenu;
    public Slider sensSlider;

    //activate once shit
    public bool activateOnce = true;

    public Slider volumeSlider;
    public void QuitToMenu(){

        Cursor.visible = true;
        SceneManager.LoadScene("MenuStuff", LoadSceneMode.Single);


    }
    public void ExitGame(){
        print("bye bye");
        Application.Quit();
    }
    public void UnPause(){
        paused = false;
    }
    public void Settings(){

        volumeSlider.value = PlayerPrefs.GetFloat("SavedVolume");
        sensSlider.value = PlayerPrefs.GetFloat("SavedSensitivity");
        settingsMenu.SetActive(true);
        GameObject myEventSystem = GameObject.Find("EventSystem");
        myEventSystem.GetComponent<UnityEngine.EventSystems.EventSystem>().SetSelectedGameObject(null);
        settingsOpen = true;
    }
    public void SettingsOff(){

        PlayerPrefs.SetFloat("SavedVolume", volumeSlider.value);
        PlayerPrefs.SetFloat("SavedSensitivity", sensSlider.value);
        settingsOpen = false;
        settingsMenu.SetActive(false);
        GameObject myEventSystem = GameObject.Find("EventSystem");
        myEventSystem.GetComponent<UnityEngine.EventSystems.EventSystem>().SetSelectedGameObject(null);

    }

    //every frame updates or smth :3
    void Update(){

        if(inRegMenu == true){
            Cursor.lockState = CursorLockMode.None;
            Cursor.visible = true;
            Time.timeScale = 1;
            //pauseMenuObj.SetActive(true);
            //playerCam.SetActive(true);
            //uiStuff.SetActive(true);
        }
        mixer.SetFloat("VolumeMain",Mathf.Log10(PlayerPrefs.GetFloat("SavedVolume"))* 20f);
        if(settingsOpen == true){
            firstSettings.SetActive(false);
        }
        else if(settingsOpen == false)
        {
            firstSettings.SetActive(true);
        }

        if(Input.GetKeyDown(KeyCode.Escape) && settingsOpen == false && inRegMenu == false){
            paused = !paused;
        }
        else if(Input.GetKeyDown(KeyCode.Escape) && settingsOpen == true){
            SettingsOff();


        }
        if(paused == true && playerCam != null){

            activateOnce = true;
            if(SceneManager.GetActiveScene().name != "MenuStuff")
            {
                AudioListener.pause = true;
            }

            Cursor.visible = true;
            Cursor.lockState = CursorLockMode.None;
            Time.timeScale = 0;
            pauseMenuObj.SetActive(true);
            playerCam.SetActive(false);
            uiStuff.SetActive(false);
        }
        else if(playerCam != null)
        {
            Cursor.lockState = CursorLockMode.Locked;
            Cursor.visible = false;
            Time.timeScale = 1;
            pauseMenuObj.SetActive(false);
            if(activateOnce == true){
                AudioListener.pause = false;
                playerCam.SetActive(true);
                uiStuff.SetActive(true);
                activateOnce = false;
            }



        }
        if(SceneManager.GetActiveScene().name == "MenuStuff"){
            UnPause();
        }

    }

}