How to get mouse direction to use in RaycastHit 2D?

Hi all. I can’t figure out how to get the right mouse direction for raycasting. The code I used below:

            var mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
            RaycastHit2D hit = Physics2D.Raycast(transform.position, mousePos);

            if (hit)
            {
                Debug.DrawLine(transform.position, hit.point, Color.red);
            }
            else Debug.DrawLine(transform.position, mousePos, Color.green);

Vector3 touchScreenPosition = Input.mousePosition;

 Ray ray = Camera.main.ScreenPointToRay(touchScreenPosition);

 if (Physics.Raycast(ray, out RaycastHit hitdata, 1000)
{
        Debug.DrawRay(ray.origin, ray.direction * 50, Color.yellow);
}