personnel accounting

using System;

internal class Program
{
    static void Main(string[] args)
    {
        const string AddDossierCommand = "add";
        const string OutputDossierCommand = "output all";
        const string DeleteDossierCommand = "delete";
        const string FindLastNameCommand = "find";
        const string EndProgramCommand = "exit";

        string[] fullNames = new string[1];
        string[] jobTitles = new string[1];
        bool isWorking = true;

        while (isWorking)
        {
            Console.WriteLine($"База данных:" +
            $"\nДля добавления досье введите - {AddDossierCommand}." +
            $"\nДля вывода всей базы введите - {OutputDossierCommand}." +
            $"\nДля удаления досье введите - {DeleteDossierCommand}." +
            $"\nДля поиска по фамилии введите - {FindLastNameCommand}." +
            $"\nДля выхода введите - {EndProgramCommand}.");

            string? userInput = Console.ReadLine();

            switch (userInput)
            {
                case AddDossierCommand:
                    AddDossier(ref fullNames, ref jobTitles);
                    break;

                case OutputDossierCommand:
                    OutputAllDossier(fullNames, jobTitles);
                    break;

                case DeleteDossierCommand:
                    DeleteDossier(ref fullNames, ref jobTitles);
                    break;

                case FindLastNameCommand:
                    FindLastName(ref fullNames, ref jobTitles);
                    break;

                case EndProgramCommand:
                    EndProgram(out isWorking);
                    break;

                default:
                    UncorrectMessage();
                    break;
            }

            Console.Clear();
        }
    }

    static void AddDossier(ref string[] fullNames, ref string[] jobTitles)
    {
        string fullName = "ФИО";
        string jobTitle = "досье";

        fullNames = FillingArray(fullNames, fullName);
        jobTitles = FillingArray(jobTitles, jobTitle);
    }

    static void OutputAllDossier(string[] fullNames, string[] jobTitles)
    {
        for (int i = 0; i < fullNames.Length - 1; i++)
        {
            if (i >= 0 && i < fullNames.Length - 2)
            {
                Console.Write($"{i + 1} {fullNames[i]} {jobTitles[i]} - ");
            }
            else
            {
                Console.Write($"{i + 1} {fullNames[i]} {jobTitles[i]}.");
            }
        }

        Console.ReadKey();
    }

    static void DeleteDossier(ref string[] fullNames, ref string[] jobTitles)
    {
        string[] newFullNames = new string[fullNames.Length - 1];
        string[] newJobTitles = new string[jobTitles.Length - 1];
        Console.Write("Введите номер досье, которое хотите удалить: ");
        int number = Convert.ToInt32(Console.ReadLine()) - 1;

        if (number <= 0 || number > fullNames.Length)
        {
            Console.WriteLine("Число вышло за пределы массива.");
        }

        for (int i = 0; i < number; i++)
        {
            FillingArraytoIndex(ref fullNames, ref newFullNames, number, out int j);
            FillingArraytoIndex(ref jobTitles, ref newJobTitles, number, out j);
        }
        for (int i = number + 1; i < fullNames.Length - 1; i++)
        {
            FillingArraytoIndex(ref fullNames, ref newFullNames, number, out int j);
            FillingArraytoIndex(ref jobTitles, ref newJobTitles, number, out j);
        }

        fullNames = newFullNames;
        jobTitles = newJobTitles;
    }

    static void FindLastName(ref string[] fullNames, ref string[] jobTitles)
    {
        Console.Write("Введите фамилию: ");
        string? lastName = Console.ReadLine();

        for (int i = 0; i < fullNames.Length - 1; i++)
        {
            if (fullNames[i].Split()[0] == lastName)
            {
                Console.WriteLine($"{i + 1} {fullNames[i]} {jobTitles[i]}");
            }
        }

        Console.ReadKey();
    }

    static void EndProgram(out bool isWorking)
    {
        Console.WriteLine("Выход из программы. Нажмите любую клавишу...");
        Console.ReadKey();
        isWorking = false;
    }

    static void UncorrectMessage()
    {
        Console.WriteLine("Введена некорректная команда. Попробуйте еще раз.");
        Console.ReadKey();
    }

    static string[] FillingArray(string[] array, string indexName)
    {
        string[] tempArray = new string[array.Length + 1];

        for (int i = 0; i < array.Length; i++)
        {
            tempArray[i] = array[i];
        }

        Console.Write($"Введите {indexName}: ");
        string? name = Console.ReadLine();
        tempArray[array.Length - 1] = name;
        array = tempArray;
        return array;
    }

    static void FillingArraytoIndex(ref string[] array, ref string[] newArray, int index, out int j)
    {
        j = 0;

        for (int i = 0; i < array.Length; i++)
        {
            if (i != index)
            {
                newArray[j] = array[i];
                j++;
            }
        }
    }
}