How to save the current scene the player is in using PlayerPrefs?

In the first scene to load create an Empty GameObject and name it "SceneHandler".

Create a new tag "SceneHandler" and add it to the "SceneHandler" GameObject

Add the following "SceneHandler" script to the "SceneHandler" GameObject

See the CustomScript script below for example usage

using System.Collections; using UnityEngine; using UnityEngine.SceneManagement;

public class SceneHandler : MonoBehaviour {

  void Awake()
     {
         DontDestroyOnLoad(gameObject);
     }
 
     public void SaveScene()
     {
         int activeScene = SceneManager.GetActiveScene().buildIndex;
 
         PlayerPrefs.SetInt("ActiveScene", activeScene);
     }
 
     public void LoadScene()
     {
         int activeScene = PlayerPrefs.GetInt("ActiveScene");
 
         //SceneManager.LoadScene(activeScene);
 
         //Note: In most cases, to avoid pauses or performance hiccups while loading,
         //you should use the asynchronous version of the LoadScene() command which is: LoadSceneAsync()
 
         //Loads the Scene asynchronously in the background
         StartCoroutine(LoadNewScene(activeScene));
     }
 
     IEnumerator LoadNewScene(int sceneBuildIndex)
     {
         AsyncOperation asyncOperation = SceneManager.LoadSceneAsync(sceneBuildIndex);
         asyncOperation.allowSceneActivation = false;
 
         while (asyncOperation.progress < 0.9f)
         {
             yield return null;
         }
 
         asyncOperation.allowSceneActivation = true;
 
     }
 }
 
 

using UnityEngine;

//EXAMPLE USAGE OF Saving/Loading of Active Scene

public class CustomScript : MonoBehaviour { private SceneHandler sceneHandler;

  void Awake ()
     {
         sceneHandler = GameObject.FindGameObjectWithTag("SceneHandler").GetComponent<SceneHandler>();
     }
 
     void CustomMethod()
     {
         sceneHandler.SaveScene();
 
         sceneHandler.LoadScene();
     }
 
 }