Itween gradual jump 2d

Hello everyone. I’m trying to make my player jump gradually while the button is pressed, but without success. Could someone give some idea of ​​how to do?
ITween use to make the player move through a path. The player has a rigidbody2d with isKinematic enabled and a gameobject child who has a renderer sprite

if (!jumping && Input.GetMouseButton(0)) {
     StartCoroutine (Jump());
 }
 
     IEnumerator  Jump (){        
         jumping = true;
         float timer = 0.0f;
         
         while (timer <= jumpTime) {
             float height = Mathf.Sin(timer / jumpTime * Mathf.PI) * jumpHeight;
             transform.localPosition = new Vector3(transform.localPosition.x, transform.localPosition.y+height, 0);
             timer += Time.deltaTime;
             
             yield return null;
         }
         jumping = false;
     }

In the editor, go to

Edit > Project settings > Physics and change Y Gravity to something in the negatives, the lower the number the greater the gravity.

Next, all you need is a code like this:

 if (Input.GetKey (YourJumpKey))
 {
 rigidbody.velocity = new Vector3 (0, JumpForce, 0);
 }