Use the commands in this section to specify which products are to appear in the Product List object.
The column on the left side of the window shows the Category and Product List inserted when the Shopping Cart was created in Step 1 - Website Settings.
There is a check box next to each category and product: click on the check boxes to add categories/products to the Product List you are creating. All the selected products are shown in the column on the right side of the window.
Selecting a category or selecting all the products in a category is not the same thing: only in the first case, if new products are subsequently added to the category you added to the Product List, they too will be added automatically to the same Product List.
You can decide how you want the products in the righthand column to be ordered: click on the Sort order button and choose Custom, First Name, Category, Price, Ascending or Descending.
If you choose Custom you can use the Move up / Move down buttons to order the products as you want them to appear.
Read the guides: