The purpose of managing stocks with authenticated staff adding and removing the stocks and giving barcodes with GTIN is to ensure accurate and efficient inventory management. By having authenticated staff members responsible for adding and removing stocks, the company can maintain control over its inventory and prevent unauthorized access or theft. Additionally, assigning barcodes with GTIN (Global Trade Item Number) to each product allows for easy tracking and identification of items, reducing the risk of errors and improving the speed of inventory management. Overall, this system helps businesses to streamline their operations, reduce costs, and improve customer satisfaction by ensuring that products are always available when needed.