There are a few possible reasons why you're not seeing your products appear. The first would be if you have multiple collections and the incorrect one is linked in the Navigation. You can double check which collection it is under Online Store>Navigation. Then select your menu and the menu item. The information will appear here.
In this spot, you'll also see the option to filter the collection by tags. Make sure any tags you add in here match up with the tags you have on your products that you want to see. Any products that don't have tags matching what is typed in here won't appear.
Another possibility is that your products aren't set to be available in the Online Store. You can check that within the product pages here.
Hopefully one of these solves the issue you're seeing, please let me know if you have any questions!