Understanding code, new to C#. How?

Question

C++ / C#

Hello :) I'm just learning the C# language and taking lessons from the MVA. They gave a DZ there, draw Koch's Snowflake with the help of a turtle, after showing some of the turtle's commands. I did everything in this way (I know that there is a lot of code that could fit in many times less, but I'm only on the threshold of the C # house and therefore, having written this code, albeit a long one, but without anyone's help, I'm glad about this):

My code

static void Main(string[] args)
        {
            var len = 5; // Размер линии
            var ugol_small = -60; // Малый угол
            var ugol_big = 120; // Большой угол
            var ugol_end = 120; // Угол поворота всей части
            Turtle.Speed = 10;
            Turtle.TurnRight();

            // Полноценная снежинка Коха

            Side4(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_end);
            Side4(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_end);
            Side4(len, ugol_small, ugol_big);
        }

        private static void Side4(int len, int ugol_small, int ugol_big) // Четвертый кусок снежинки - Окончательный
        {
            Side3(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_small);
            Side3(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_big);
            Side3(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_small);
            Side3(len, ugol_small, ugol_big);
        }

        private static void Side3(int len, int ugol_small, int ugol_big) // Третий кусок снежинки
        {
            Side2(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_small);
            Side2(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_big);
            Side2(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_small);
            Side2(len, ugol_small, ugol_big);
        }

        private static void Side2(int len, int ugol_small, int ugol_big) // Второй кусок снежинки
        {
            Side1(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_small);
            Side1(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_big);
            Side1(len, ugol_small, ugol_big);
            Turtle.Turn(ugol_small);
            Side1(len, ugol_small, ugol_big);
        }

        private static void Side1(int len, int ugol_small, int ugol_big) // Первый кусок снежинки
        {
            Turtle.Move(len);
            Turtle.Turn(ugol_small);
            Turtle.Move(len);
            Turtle.Turn(ugol_big);
            Turtle.Move(len);
            Turtle.Turn(ugol_small);
            Turtle.Move(len);
        }
    }

Further in the next lesson, the teacher showed how he made this snowflake and then I had a stupor and not understanding. In the teacher's code, I left comments, there are questions!

Teacher code

static void Main(string[] args)
        {
            Turtle.Speed = 10;
            for (int i = 0; i < 3; i++)
            {
                Draw(150, 3); // Тут по моему понимаю, задались параметры для процедуры Draw
                Turtle.Turn(120);
            }

            
        }

        public static void Draw(int len, int n) // Тут он создал процедуру Draw
        {
            if (n == 0) Turtle.Move(len); // Тут я понял, что если переменная n равна нулю, то всего лишь рисовать линию длинной равной переменной len

            else // А вот тут у меня ступор пошел.
            {
                Draw(len / 3, n - 1); // Как черепашка рисует, если нет команды Turtle.Move();
                Turtle.Turn(-60);
                Draw(len / 3, n - 1); // Как черепашка рисует, если нет команды Turtle.Move();
                Turtle.Turn(120);
                Draw(len / 3, n - 1); // Как черепашка рисует, если нет команды Turtle.Move();
                Turtle.Turn(-60);
                Draw(len / 3, n - 1); // Как черепашка рисует, если нет команды Turtle.Move();
            }

        }

And if someone does not understand, the question specifically concerns this: Draw(len / 3, n - 1); // How the turtle draws if there is no command Turtle.Move();
How does the turtle draw a line if there is no Turtle.Move() command for it;

Answer 1

there is a recursion.
public static void Draw(int len, int n) {
...
Draw(len / 3, n - 1);
...
Here Draw means that the Draw function will be called again, but with "n-1"
If n is equal to 0, and this happens on the third nested Draw call, then the command with move will be called.