As soon as Store Commander is installed on your PrestaShop store, you'll see a category called Sc Recycle Bin, automatically created, at the same level as Home.
It can be identified by the icon
Although you can defintely delete products off your shop using the option , you have the possibility to drag products to the Recycle bin. At this point, products will not be removed from the database, and can be moved back to a categoy if need be.
Deleting products definitely will occur when you empty the Recycle Bin, using the corresponding icon located on the category toolbar. At this point, products present in the Recycle Bin will definitely be deleted off your shop.
Note that products present in the Recycle Bin will be definitely deleted off the database if and only if they're not present in any other categories. If a product exists in another category, then it will not be deleted.
Categories can also be dragged to the Recycle bin, and will also be definitely removed from the shop when the bin is emptied.
Note: if the Recycle Bin has been emptied by mistake, and therefore categories and products contained have been deleted, the only solution to get them back is to restore a database backup. At this point, you'll need to contact your web agency or service provider who will be able to help you with this procedure.