Hi, In this video I will show how to create platform that falls after player will jump on it.

Link to video:

Code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class FallingPlatform : MonoBehaviour
{
    public float TimeUntilFall;

    private void OnTriggerEnter2D(Collider2D collision)
    {
        if (collision.gameObject.CompareTag("Player"))
        {
            Invoke("Fall", TimeUntilFall);
        }
        
    }

    public void Fall()
    {
        if (gameObject.GetComponent<Rigidbody2D>() != null)
        {
            gameObject.GetComponent<Rigidbody2D>().bodyType = RigidbodyType2D.Dynamic;
        }
        
    }
}