Stage's Complicated File Renamer :^)

Program.cs

using System;
using System.IO;
using System.Linq;

namespace FileChallenge
{
    class Program
    {
        static void Main(string[] args)
        {
            var file = $"{Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}/text.txt";

            if (File.Exists(file))
            {
                Console.WriteLine("Welcome to the file renamer!");
                Console.WriteLine($"File to Rename: {file}");
                Console.WriteLine();
                Console.WriteLine("What would you like to rename your file to?");

                var newName = Console.ReadLine();

                Console.WriteLine("Got it.");

                var fileName = newName.Split('.').First();
                var fileSuffix = newName.Split('.').Last();

                string newFileNameString = "";

                foreach (char letter in fileName)
                {
                    newFileNameString += letter;
                }

                if(!newFileNameString.Contains(".txt"))
                    newFileNameString += ".txt";

                var newFileLocation = $"{Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}/{newFileNameString}";

                File.Copy(file, newFileLocation, true);
                File.Delete(file);

                Console.WriteLine("Successfully renamed the file!");
            }
            else
            {
                File.OpenWrite($"{Environment.GetFolderPath(Environment.SpecialFolder.Desktop)}/text.txt");
                Console.WriteLine("I didn't find that file so I created it!");
            }
        }
    }
}