left and right buttons for android 2d game

i used this code to allow my player to move left and right but i don't know how to include the codes for buttons...i'm just a beginner at this...i would like to credit "gucio devs" since the code i got was from his tutorial...thanks please reply asap :)

 using UnityEngine;
 using System.Collections;
 
 public class Touch : MonoBehaviour {
     public float speed=5f;
     public bool grounded;
     private Rigidbody2D rb2d;
     
     
     // Use this for initialization
     void Start () {
         rb2d = gameObject.GetComponent<Rigidbody2D> ();
     }
     
     // Update is called once per frame
     void Update () {
         
     }
     void FixedUpdate()
     {
         float h = Input.GetTouch ("Horizontal");
         rb2d.AddForce ((Vector2.right * speed) * h);
     }
 }