How would I change the rotation by 90 degrees of the transform.rotation?

I want to change the of the rotation of the transform.rotation as my 2d gameobject is facing the wrong way`

public class MoveForward : MonoBehaviour {

public float maxSpeed = 5f;



void Update () {
    
	Vector3 pos = transform.position;
   
	Vector3 velocity = new Vector3(0, maxSpeed * Time.deltaTime, 0);
	
	pos += transform.rotation * velocity;

	transform.position = pos;
}

}
`.

Not tested :

transform.eulerAngles = new Vector3(xRotation, yRotation, zRotation);

Just set your rotation parameter and 0 to the others (not sure if it’s an angle but you can try using 90)