Excel Business Simple Project

Please read the following requirements to be able to do the project... * The file has two sheets: Inventory and Invoice. Inventory is the stock of the products, and Invoice is the bill for customers when someone purchases something, I will fill it out. * The idea of this project, whenever I use the scanner to scan the barcode (Only numbers) that was saved in Inventory sheet; The scanned barcode should give from Inventory to the Invoice sheet as follow:
the Barcode scanned number, Product ID, Product Name, Product Picture as well (I will put pictures), Wholesale Price Per Piece, and Selling Price. You need to link Inventory and Invoice sheets. 
 * Quantity in Inventory should be automatically subtracted and updated whenever I put Quantity in Invoice sheet. 
 * In Inventory sheet whenever I scan a product that is already existed it should be updated and not to add it again or duplicated. * Please make sure the file is working on Google Sheets as well. So, the idea is just like supermarket, and here I will give an example to clarify the idea more. For example, if I have a product that its Barcode number is already registered in Inventory, and someone purchased this product. So, I need to open the invoice sheet, and scan the barcode, this barcode should give me from Inventory sheet; Barcode scanned number, Product ID, Product Name, Product Picture, Wholesale Price Per Piece, and Selling Price. And Quantity in Inventory should be automatically updated and subtracted from Quantity I put in Invoice.