create a bool Attack with two int variables and ask user for input

static void Main(string[] args)
{
    Console.WriteLine("Do you want to attack?");
    string answer = Console.ReadLine();

    if (answer == "yes")
    {
        Console.WriteLine("How much health do you have?");
        int health = int.Parse(Console.ReadLine());

        Console.WriteLine("How much damage do you want to do?");
        int damage = int.Parse(Console.ReadLine());

        Console.WriteLine("Your new health is: " + (health - damage));
    }
}