---

Stopwatch.cs

using UnityEngine;
using TMPro;
 
public class Stopwatch : MonoBehaviour
{
    public bool hasFinished;
    float minutes;
    float seconds;
 
    public TextMeshProUGUI stopwatch;
 
    void Update()
    {
 
        if (hasFinished == false)
        {
            seconds += Time.deltaTime;
 
            if (seconds >= 60)
            {
                minutes += 1;
                seconds -= 60;
            }
 
        }
 
        int m = Mathf.RoundToInt(minutes);
        int s = Mathf.RoundToInt(seconds);
 
        stopwatch.text = m + ":" + s;
    }
}

Finish.cs

using UnityEngine;
 
public class Finish : MonoBehaviour
{
    public Stopwatch time;
    public RoutePoint finishPoint;
 
    private void OnTriggerEnter(Collider other)
    {
        if (finishPoint.isActiveForPlayer)
        {
            if (other.tag == "Player")
            {
                time.hasFinished = true;
            }
        }
    }
}

RoutePoint.cs

using UnityEngine;
 
public class RoutePoint : MonoBehaviour
{
    public RoutePoint nextPoint;
 
    public GameObject model;
 
    public bool isActiveForPlayer;
 
    private void OnTriggerEnter(Collider other)
    {
        if (other.tag == "Player")
        {
 
            if (isActiveForPlayer)
            {
                isActiveForPlayer = false;
                model.SetActive(false);
 
                if (nextPoint != null)
                {
                    nextPoint.isActiveForPlayer = true;
                    nextPoint.model.SetActive(true);
                }
            }
        }
    }
}