Looking for a way to rotate an object

I need to write a script where when A is pushed an object will rotate as long as its held down towards the left and when D is pushed the same will happen but it will rotate towards the right, But the thing is… I don’t know how to do that, I’m looking for some help

Here you go @Vojin2005 :

void Update () {
        var speed = 20;
        if (Input.GetKey(KeyCode.A))
        {
            transform.Rotate(0, speed * Time.deltaTime, 0);
        }
        if (Input.GetKey(KeyCode.D))
        {
            transform.Rotate(0, -speed * Time.deltaTime, 0);
        }
    }