WTF

using System;
using System.Collections.Generic;
namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            string userInput;
            Seller seller = new Seller();
            Player player = new Player();

            while (true)
            {
                Console.ReadKey();
                Console.Clear();
                seller.ShowProducts();
                Console.Write("\nВведите название продукта: ");
                userInput = Console.ReadLine();
                seller.SellProduct(userInput);
                player.ShowInventory();
            }
        }

        class Player
        {
            private List<Product> _playerInventory = new List<Product>();

            public void AddProduct(string item)
            {
                _playerInventory.Add(new Product(item));
            }

            public void ShowInventory()
            {
                for (int i = 0; i < _playerInventory.Count; i++)
                {
                    _playerInventory[i].ShowProduct();
                }
            }
        }

        class Seller
        {
            Player player = new Player();
            private List<string> _products = new List<string>() { "Руда", "Альманах", "Руна телепортации", "Глаз Инноса" };

            public void ShowProducts()
            {
                for (int i = 0; i < _products.Count; i++)
                {
                    Console.WriteLine($"{i+1}.{_products[i]}");
                }
            }

            public void SellProduct(string userInput)
            {
                bool isFind = false;
                foreach (string item in _products)
                {
                    if (item == userInput)
                    {
                        player.AddProduct(item);
                        isFind = true;
                        break;
                    }
                }
                if (isFind == false)
                {
                    Console.WriteLine("Продукт в списке не найден");
                }
            }
        }

        class Product
        {
            private string _name;

            public Product(string name)
            {
                _name = name;
            }

            public void ShowProduct()
            {
                Console.WriteLine(_name);
            }
        }
    }
}