There can be some reasons why you cannot see the products on your new installed Prestashop CMS.
To fix this issue, you need to do some settings changes in admin panel.
This issue is related to old themes that are not compatible with Smarty 3 (a php framework that the latest Prestashop versions is using).
There is an option in admin panel at the “preferences” tab (main page), the last option: “Use Smarty 2 instead of 3” with this description: “Enable if your theme is incompatible with Smarty 3 (you should update your theme, since Smarty 2 will be unsupported from PrestaShop v1.5)”.
Select “yes” there if you think that your Prestashop theme is old. This should fix the issue no matter if you use friendly SEO URLs or not.
Check a page with the products to see if the issue was fixed.