How do I call a C# Function by HTML in ASP.Net MVC

public class HomeController : Controller
   {
     private  static Random rand = new Random();
     private string _randomnumber;



       public ActionResult Index()
       {
           return View();

       }

public int Random()
{
for (int i = 0; i < 2; i++)
           {
             _randomnumber= (Convert.ToString(rand.Next(1000, 9900)));
              return new JsonResult { Data = _randomnumber, JsonRequestBehavior = JsonRequestBehavior.AllowGet };


           }
return _randomnumber;
}

<input type ="button" onclick=" GetMessage() " value=" Get Message"/>
        <p></p>
        <script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
        <script>
            function GetMessage() {

                $.get("/{HomeControlle}r/{Random}", function(data) {
                    $("p").html(data);
                });
            }


        </script>