How to add text to cubes generated through c# script

Hello, I am working on a bar chart application in which I am plotting bar chart using cube. I want to display the value for each cube as a text on the cube surface. How can I do this in c# script.

below is the code I am using for plotting chart:

void Start() { alColor.Add(Color.red); alColor.Add(Color.green); alColor.Add(Color.blue); ArrayList alData = TextRead(Application.dataPath + "/Scripts" + "/ChartData.txt"); generateColoredCubeSquare(alData); }

 private float x1, y1;
 private float z1;
 private int i = 0;
 private float x = 0, z = -70;
 private GameObject cube;

 public void generateColoredCubeSquare(ArrayList a)
 {
     int ColorIndex = -1;
     foreach (String[] o in a)
     {

         if (o.Length > 1)
         {
             x1 = float.Parse(o[0]);
             y1 = float.Parse(o[1]);
             z1 = float.Parse(o[2]);
             //LineRenderer LineRenderer = new LineRenderer();
             //LineRenderer.material.color = Color.red;

             cube = GameObject.CreatePrimitive(PrimitiveType.Cube);
             //if (ColorIndex == 0)
             //{
             cube.transform.position = new Vector3(x, 1, z);
             //}
             //if (ColorIndex == 1)
             //{
             //    cube.transform.position = new Vector3(x * (-1), 1, z);
             //}
             //else
             //{
             //    cube.transform.position = new Vector3(x, 1, z * (-1));
             //}
             cube.transform.localScale = new Vector3(x1, y1, z1 / 4);
             //cube.transform.position = new Vector3(x, cube.transform.localScale.y / 2, z);
             MeshRenderer rend = cube.GetComponent<MeshRenderer>();
             rend.material.color = (Color)alColor[ColorIndex];

             //TextMesh variableForPrefab = (TextMesh)Resources.Load("Assets/Prefabs/Prefab");
             //TextMesh txtMesh = (TextMesh)Instantiate(variableForPrefab);
             ////TextMesh txtMesh = txtMeshTransform.GetComponent<TextMesh>();
             //cube.AddComponent<TextMesh>();
             //txtMesh.text = "New text set through script";

             //TextMesh tm = cube.AddComponent<TextMesh>();
             //tm.transform.parent = cube.transform;
             //tm.text = y1.ToString();
            
             
             

             x = x + 5f;

         }
         else
         {
             ColorIndex = ColorIndex + 1;
             x = (ColorIndex * 10) + 10;
             z = z + 50;
         }

     }

 }

 private ArrayList TextRead(string fileName)
 {
     string[] entries = null;
     ArrayList alData = new ArrayList();
     // Handle any problems that might arise when reading the text
     try
     {
         string line;

         // Create a new StreamReader, tell it which file to read and what encoding the file
         // was saved as
         StreamReader theReader = new StreamReader(fileName, Encoding.Default);
         // Immediately clean up the reader after this block of code is done.
         // You generally use the "using" statement for potentially memory-intensive objects
         // instead of relying on garbage collection.
         // (Do not confuse this with the using directive for namespace at the 
         // beginning of a class!)
         using (theReader)
         {
             // While there's lines left in the text file, do this:
             do
             {
                 line = theReader.ReadLine();

                 if (line != null)
                 {
                     // Do whatever you need to do with the text line, it's a string now
                     // In this example, I split it into arguments based on comma
                     // deliniators, then send that array to DoStuff()
                     entries = line.Split(',');
                     alData.Add(entries);

                     if (entries.Length > 0)
                     {


                     }
                 }
             }
             while (line != null);
             // Done reading, close the reader and return true to broadcast success    
             theReader.Close();
             return alData;
         }
     }
     // If anything broke in the try block, we throw an exception with information
     // on what didn't work
     catch (Exception e)
     {
         Console.WriteLine("{0}\n", e.Message);
         return null;
     }
 }