C# Console.Readkey - wait for specific input

KeyChar is a char while "Y" is a string.

You want something like KeyChar == 'Y' instead.

Check this instead

string result = Console.ReadLine();

And after check the result

What your looking for is something like this

       void PlayAgain()
    {
        Console.WriteLine("Would you like to play again? Y/N: ");
        string result = Console.ReadLine();
        if (result.Equals("y", StringComparison.OrdinalIgnoreCase) || result.Equals("yes", StringComparison.OrdinalIgnoreCase))
        {
            Start();
        }
        else
        {
            Console.WriteLine("Thank you for playing.");
            Console.ReadKey();
        }
    }