1. Scan the barcode of the products

2. If the customer buys multiple quantities of the same product, just scan the barcode by the number of items or click on Qty and choose the quantity bought

3. You can also search the products by typing the product name and/or barcode.

4. Change the quantity by making sure the purple bar is on Qty and change the quantity accordingly.

You can also watch this video for reference: https://screencast-o-matic.com/watch/c0fFI4Vzflg