To manage products:
Go to "Inventory" from the menu, then click Products.
On the Products page, you'll see the list of the products created.
Click on the product name you want to manage.
After clicking on the product you want to manage, the details of the product will show and you can click on Edit.
On the next page, can change/add details of the product. Once done, click Submit. The changes made will be saved.