click the menu item System Settings/Basic Coding Settings/User-defined Goods and Services Coding to open the Commodity Coding window. In the "Commodity Code" window, you can add, edit, delete, query and a series of editing operations on commodity code data. Click "Add Commodity" to open the "Add Commodity" window, enter the name, specifications, unit and unit price in turn, and click "Submit Now". After adding the goods, click the "Assign Code" button to add the tax code for the goods. Enter commodity keywords and click the "Search" button. Select the matching commodity code, click OK, and the code assignment is completed.