Jeremy/Assets/Scripts/SceneSwitcher.cs

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class SceneSwitcher : MonoBehaviour
{
    // make singleton
    public static SceneSwitcher Instance { get; private set; }
    
    private void Awake()
    {
        SetInstance();
    }

    private void OnValidate()
    {
        SetInstance();
    }

    private void SetInstance()
    {

        if (Instance == null)
        {
            Instance = this;
        }
        else
        {
            Debug.LogError("SceneSwitcher Instance already exists.");
        }
    }

    [SerializeField]
    private GameObject[] _deactivateChildrenOf;

    public void SwitchScene(int sceneIndex)
    {
        for (var i = 0; i < transform.childCount; i++)
        {
            transform.GetChild(i).gameObject.SetActive(i == sceneIndex);
        }
        
        foreach (var toDeactivate in _deactivateChildrenOf)
        {
            foreach (Transform child in toDeactivate.transform)
            {
                child.gameObject.SetActive(false);
            }
        }
    }

    public void SwitchToNext()
    {
        for (var i = 0; i < transform.childCount; i++)
        {
            if (transform.GetChild(i).gameObject.activeSelf)
            {
                var nextIndex = i + 1;
                if (nextIndex >= transform.childCount)
                {
                    nextIndex = 0;
                }
                SwitchScene(nextIndex);
                return;
            }
        }
    }
    
    public List<(string name, int index)> GetScenes()
    {
        var scenes = new List<(string name, int index)>();
        for (var i = 0; i < transform.childCount; i++)
        {
            var child = transform.GetChild(i);
            scenes.Add((child.name, i));
        }
        return scenes;
    }
    public GameObject GetGameObject(int sceneIndex)
    {
        return transform.GetChild(sceneIndex).gameObject;
    }
}