Bank program help

using System;

class Bank
{
    static void Main()
    {
        Console.WriteLine("Welcome to the bank. Please select one of the given options.");
        Console.WriteLine("1. Withdraw money");
        Console.WriteLine("2. Deposit money");
        Console.WriteLine("3. Check balance");
        Console.WriteLine("4. Send money");

        int balance = 0;
        int option = int.Parse(Console.ReadLine());

        while (option >= 5)
        {
            Console.WriteLine("Please choose a valid option.");
            option = int.Parse(Console.ReadLine());
        }

        if (option == 1)
        {
            Console.WriteLine("Please write the amount of money you are gonna withdraw.");
            int amount = int.Parse(Console.ReadLine());
            Console.WriteLine("Withdrawing " + amount + "...");

            balance -= amount;

            Console.WriteLine("Your new balance is " + balance + ".");
        }

        if (option == 2)
        {
            Console.WriteLine("Please write the amount of money you are gonna deposit.");
            int amount = int.Parse(Console.ReadLine());
            Console.WriteLine("Depositing " + amount + "...");

            balance += amount;

            Console.WriteLine("Your new balance is " + balance + ".");
        }




    }
}