So, it should look like this?

Code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            int number;
            int guess;
            int.TryParse(Console.ReadLine, out guess);
            Random rand;
            rand = new Random();

            number = rand.Next(1, 3);

        Start:
            do
            {
                Console.WriteLine("Guess the number from 1 to 3.");
                guess = Console.ReadLine();

                if (guess == number)
                {
                    Console.WriteLine("You've won.");
                }

                else
                {
                    Console.WriteLine("Sorry, guess again.");
                    goto Start;
                }
            } while (guess != "Q");
        }
    }
}