Prestashop 1.6.x. How to manage Inventory

1. In your PrestaShop admin panel go to Catalog -> Products section: 
2. Find the product you want to edit and click the Edit button: 
3. In the Quantities tab, you can see the available product quantities: 
4. In the Warehouses tab available warehouses for the product storage are displayed. The tab does not have quantities listed but you can check/uncheck the warehouse assignment: 
5. Go to Preferences -> Products section: 
6. In Product page section you can set the following options:
   • Display available quantities on the product page – enable/disable the inventory display on the site;
   • Display remaining quantities when the quantity is lower than – set your number for frontend display:
7. In Product Stock section such settings can be managed:
   • Allow ordering of out-of-stock products – enable/disable;
   • Enable stock management – enable/disable;
   • Enable advanced stock management – allows you to manage physical stock, warehouses and supply orders in a new Stock menu;
   • New products use advanced stock management – enable/disable;
   • Default warehouse on new products – automatically set a default warehouse when new product is created:
8. If you have Advanced Stock Management enabled, you can also manage inventory in Stock -> Stock Management.

Hopefully, this tutorial was helpful for you.