forellenforderung3/Assets/AssetsFORELLE/Script/MainMenu.cs

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

public class MainMenu : MonoBehaviour
{
    private int selectedLevel;

    private Dictionary<int, int> levels = new Dictionary<int, int>()
    {
        {1,   1},
        {2,   2},
        {3,   3},
        {4,   4},
        {5,   7},
        {6,  10},
        {7,  11},
        {8,  12},
        {9,  13},
        {10, 14},
        {11, 15},
        {12, 16},
        {13, 21}
    };

    public void startGame()
    {
        Debug.Log("Main Menu: New Game");
        SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex+1);
    }

    public void endGame()
    {
        Debug.Log("Main Menu: Quit Game");
        Application.Quit();
    }

    public void setSelectedLeve(int level)
    {
        selectedLevel = ++level;
    }

    public void loadScene()
    {
        Debug.Log("Main Menu: Load Level " + levels[selectedLevel]);
        SceneManager.LoadScene(levels[selectedLevel]);
    }
}