How can I save and load the last loaded scene in Json?

Hi guys, so I want to save and load the last loaded scene that I was in in my project, so when I click load it starts me in the scene I last saved in.

I already did this with Playerprefs but I want to do it with Json. This is how I’ve done it until now:

my save:

void OnApplicationQuit()
{
    PlayerPrefs.SetInt("SavedScene", SceneManager.GetActiveScene().buildIndex);
    SaveGame();
}

from continue button in the menu:

public void OnContinueGameClicked()
{
    DisableMenuButtons();
    DataPersistenceManager.instance.SaveGame();
    SceneManager.LoadSceneAsync(PlayerPrefs.GetInt("SavedScene"));
}

from my load save button:

public void OnSaveSlotClicked(SaveSlot saveSlot)
{
    DisableMenuButtons();      DataPersistenceManager.instance.ChangeSelectedProfileId(saveSlot.GetProfileId());    
    if(!isLoadingGame)
    {
        DataPersistenceManager.instance.NewGame();
    }
    SceneManager.LoadSceneAsync(PlayerPrefs.GetInt("SavedScene"));
}