How to AddForce to a GameObject with Touch

Here’s my funtion :

public float sideforce = 80f;

void FixedUpdate()
{

    if (Input.GetKey("a")) // Ball Turns Left
    {
        rb.AddForce(-sideforce * Time.deltaTime, 0, 0, ForceMode.VelocityChange);
    }

    if (Input.GetKey("d")) // Ball Turns right
    {
        rb.AddForce(sideforce * Time.deltaTime, 0, 0, ForceMode.VelocityChange);
    }

}

Question : As you can see my ball moves left and right with keys “a” and “d”. But I’m developing a game for mobile. So, I want to replace those keyboard controls with touch controls.

Please help me out.

Have you checked out the mobile and touch tutorials?

https://unity3d.com/learn/tutorials/s/mobile-touch

Not something I’ve had to look at myself yet but it’s where I’d start