how to write a code for withdrawal using C#

Just simple store the input which you have after readline and convert it into double and then subtratc it from the original balance and display the remaining balance.

double OriginalBalance = 10000;

Console.WriteLine ("How much you'd like to Withdraw");

double AmmountWithdraw = double.Parse(Console.ReadLine());

OriginalAmmount -= AmmountWithdraw;

Console.WriteLine("Your Remaining balance:" + OriginalAmmount.ToString());

If you'd like i have a C++ project which does the same i can share that with you.