Shuffle

    class Program
    {
        static void Main(string[] args)
        {
            int arrayLength = 10;
            int[] arrayNumbers = new int[arrayLength];

            FillArrayNumbers(arrayNumbers);

            Print(arrayNumbers);

            ShuffleArray(arrayNumbers);

            Print(arrayNumbers);

            Console.ReadLine();
        }

        private static void FillArrayNumbers(int[] arrayNumbers, int maxNumber = 20, int minNumber = -20)
        {
            Random random = new Random();

            int randomNumber = minNumber;

            for (int i = 0; i < arrayNumbers.Length; i++)
            {
                randomNumber = random.Next(minNumber, maxNumber + 1);

                arrayNumbers[i] = randomNumber;
            }
        }

        private static void Print(int[] arrayNumbers)
        {
            foreach(int number in arrayNumbers)
            {
                Console.Write(number + " ");
            }

            Console.WriteLine();
        }


        private static void ShuffleArray(int[] arrayNumbers)
        {
            Random random = new Random();

            int index = 0;
            int numberBuffer = 0;

            for (int i = 0; i < arrayNumbers.Length; i++)
            {
                index = random.Next(0, arrayNumbers.Length);

                numberBuffer = arrayNumbers[index];
                arrayNumbers[index] = arrayNumbers[i];
                arrayNumbers[i] = numberBuffer;

                Console.WriteLine($"{i}  -  Рандомный индекс: {index}; Число под индексом {index}: {numberBuffer}; Число которое поменяли: {arrayNumbers[index]}");
            }
        }
    }