How can add “Warm up” in unity 2d game?

Questions & Answers
1

Hi everyone!
I want add “Warmup” to my game like Counter strike Warmup.
I want that after 30 sec game start and restart player to original position and there is not timer anymore in the game.
How can I Do? I use this line too but not working:

    if (cuurentTime == 0)
    {
        SceneManager.LoadScene(SceneManager.GetActiveScene().buildIndex);
    }

but is not working. I use this cod:

public class TimerCountDown : MonoBehaviour
{
    float cuurentTime = 0f;
    float startingTime = 30f;

    [SerializeField] Text CountDownText;
    
    void Start()
    {
        cuurentTime = startingTime;

    }

    void Update()
    {

        cuurentTime -= 1 * Time.deltaTime;
        CountDownText.text = cuurentTime.ToString("0");

        if (cuurentTime <= 0)
        {
            cuurentTime = 0;
        }
       
    }
     
}
2

this method would be better for a 2d game.

using System.Collections;
using UnityEngine;

public class TimerCountDown : MonoBehaviour
{

    private void Start()
    {
        StartCoroutine(StopAndStartGame()); 
    }

    IEnumerator StopAndStartGame()
    {
        Time.timeScale = 0;       // for stop game

        yield return new WaitForSecondsRealtime(30); // wait 30 second (realtime.. Because game is stoped.)

        Time.timeScale = 1;      // for start game
    }
}

OR

using UnityEngine;
using UnityEngine.UI;

public class TimerCountDown : MonoBehaviour
{

    float counter;

    [SerializeField]
    Text textCounter ;

    bool warmupOn;

    private void Start()
    {
        counter = 30;
        warmupOn = true;
    }
    private void Update()
    {

        if (warmupOn == true)
        {
            counter -= Time.deltaTime;
            textCounter.text = Mathf.Ceil(counter).ToString();
            Debug.Log("starting");

            if (counter == 0 || counter < 0)
            {
                Debug.Log("stoped");
                warmupOn = false;

                // Load Scene or Your Restart Method.
            }
        }

    }

}