How do you detect if a touch is hitting an object?

Hi,
i have a 2d project that is running on android (via unity remote 5)
and i'm trying to detect when the player is touching an object.

The following is my code:

     void Update()
     {
         foreach(Touch touch in Input.touches)
         {
             if(touch.phase == TouchPhase.Began)
             {
                 Debug.Log("touch");
                 RaycastHit2D hit = Physics2D.Raycast(touch.position, Vector2.zero, Mathf.Infinity);
 
                 if (hit.collider)
                     Debug.Log("hit");
             }
         }
         
     }

The problem is that it never prints "hit" - even when im actually pressing an object.

The only problem i can see with the code is that Physics2D.Raycast takes in a vector2d
as the direction, but the direction it should raycast in is in the z direction.

But i heard you could get around that if you passed in a zero vector (which is what im doing) but it still doesn't seem to work.

I would really appreciate it if somebody could tell me why it isn't working.
Thanks in advance!