Unity implements buttons to control character movement

In unity development, we often use buttons to implement certain functions, such as wasd to control the movement of characters, how to achieve it? code show as below:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class KeysMove : MonoBehaviour
{
// Start is called before the first frame update
void Start()
{

}

// Update is called once per frame
void Update()
{
control();

}
public void control()
{
if (Input.GetKey(KeyCode.W))
{
this.transform.Translate(Vector3.forward);
//gameObject.transform.Translate(0, 0, move, Space.Self);

}
else if (Input.GetKey(KeyCode.S))//press keyboard s to move down
{ this.transform.Translate(Vector3.back); }

if (Input.GetKey(KeyCode.A))//Press keyboard a to move to the left
{ this.transform.Translate(Vector3.left); } else if (Input.GetKey(KeyCode.D))//Press keyboard d to right shift { this.transform.Translate(Vector3.right); } }

}