10x10 drawing grid 2.0

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

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            //init

            bool c = true; char Change = ' '; char y = ' '; char x = ' ';string Schange;int posx = 0; int posy = 0;
            char[][] board;

            board = new char[10][];
            for (int n = 0; n < 10; n++)
            {
                board[n] = new char[10];
            }


            //set all as blank
            for (int ix = 0; ix < 10; ix++)
            {
                for (int iy = 0; iy < 10; iy++)
                {
                    board[ix][iy] = ' ';
                }
            }

            //init end


            while (true)
            {



                Console.WriteLine("  A B C D E F G H I J");
                char posY = 'A';
                for (int ix = 0; ix < 10; ix++)
                {
                    Console.Write(posY);
                    for (int iy = 0; iy < 10; iy++)
                    {
                        Console.Write(" " + board[ix][iy]);
                    }
                    Console.Write("\n");
                    posY++;
                }







                //select

                Console.Write("x:");
                var Kx = Console.ReadKey();
                x = char.Parse(Kx.Key.ToString());
                Console.WriteLine("");

                Console.Write("y:");
                var ky = Console.ReadKey();
                y = char.Parse(ky.Key.ToString());
                Console.WriteLine("");


                if(x - 'A' >= 0)
                {
                    posx = x - 'A';
                }else if (x - 'a' >= 0)
                {
                    posx = x - 'a';
                }

                if (y - 'A' >= 0)
                {
                    posy = y - 'A';
                } else if (y- 'a'>= 0)
                {
                    posy = y - 'a';
                }

                Console.Write("Vad ska den vara:");
                try
                {
                    Change = char.Parse(Console.ReadLine());
                }
                catch (FormatException e)
                {
                    Console.WriteLine("Fel format!");
                    Change = board[posx][posy];
                }

                board[posx][posy] = Change;

            }
        }
    }
}