[C#] Number game (My little brother coded it)

[Bman]

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

namespace Number_Game
{
    class Program
    {
        static void Main(string[] args)
        {
            String Frst,Second,Guess;
            int First,Secnd,gyuss,outtie;
            Random rndi = new Random();
            Console.WriteLine("welcome to the number guessing game.");
            Frst = Console.ReadLine();
            Second = Console.ReadLine();
            Secnd = int.Parse(Second);
            First = int.Parse(Frst);
            outtie = rndi.Next(First, Secnd);
            Console.WriteLine("Please guess a number : ");
            Guess = Console.ReadLine();
            gyuss = int.Parse(Guess);
            if (outtie == gyuss)
            {
                Console.WriteLine("You win! ;D");
                Console.ReadKey();
            }
            else
            {
                Console.WriteLine("Fail");
                Console.ReadKey();
            }
        }
    }
}