How can I use barcode on existing Excel !

Hello all,

I have this excel with Ref codes (bar code numbers) and I need to use the bar code that I bought (ZKTECO Omni Direction Barcode Scanner) if someone want to buy any product by just scanning the bar code of the product with subtracting the Quantity of the products without scanning all the products and entering theme manually as they are already exist on the excel.

Thank you

BL.xls