Inventory Management using barcode

Hello, I am attempting to make a stock number using a barcode scanner.

I know that there is a similar thread, but I do not understand anything, so can someone please explain in a more simple way?

The difference is when I scan items, the count goes up automatically, I don't mind to make 3 columns with one that goes up and the other goes down and the third one is total.

Feel free to ask any specifications, but I might not understand the question. Thank you!

Welcome to the forum!

Post a sample WORKBOOK. Nobody wants to type data from a picture or paste text from your post into a spreadsheet as a prelude to helping. To attach a file, click Go Advanced below the text edit window, scroll down and click the Manage Attachments link, browse to the required file, and then push the Upload button, then Close Window to return to your post. (The "paper clip" icon for attachments is not currently working.)

Thank you for your tip! I have the attachment, so basically, when I scan a barcode, I want that specific item number to go up by one, without using a button to write add/sub.