how to make mouse in unity 2d code example

Example 1: Point to mouse 2D Unity

Vector3 difference = Camera.main.ScreenToWorldPoint(Input.mousePosition) - transform.position;
        difference.Normalize();
        float rotation_z = Mathf.Atan2(difference.y, difference.x) * Mathf.Rad2Deg;
        transform.rotation = Quaternion.Euler(0f, 0f, rotation_z + offset);

Example 2: unity 2d how to set an object or the mouse position

Vector2 mousePos = new Vector2(camera.ScreenToWorldPoint(Input.mousePosition.x), camera.ScreenToWorldPoint(Input.mousePosition.y));