Create virtual keyboard on screen

Hi, I was wondering how to create a virtual keyboard manually, using buttons. when click to the buttons, text appear on screen. I created a code, but it only appear one letter only. How I could appear the text according to button click?
67829-keyboard.png

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

public class textAnswer : MonoBehaviour {

	public Text Alphabet;

	public void firstgame (string alphabet) {
		Alphabet.text = alphabet;
		string firstGameResult = alphabet;
		
		if (firstGameResult == "e") {
			Debug.Log ("correct");

			}

You’re always overwriting the text value of Alphabet. You could try something like:

Alphabet.text += alphabet;

This will append the text.