If you want to add multiple items from a selected page, without the Point of Sale menu returning to the main category page, use the setting Stay On Last Item. This helps reduce the number of buttons your cashier needs to select.
After adding an item to the order, the menu will reside on the last selected item. If this setting is not enabled, your menu screen will return to the main category page. Adjust this feature under Settings > Stay On Last Item. When completed, click Save.