To duplicate a product, proceed to your Product Catalog. Duplicating products is always helpful as same item could be carried by multiple manufacturers, and might have different pricing or cheaper shipping or hundred other reasons that I might want to make a copy of the item in my catalog to then edit and suggest it to my clients.
There are multiple way to duplicate a product and the video shows all these methods.
However, to summarize, you can duplicate a product from:
1) Click on the 3 dots on the product from the Catalog to duplicate.
2) When in the product page, there is an option to Duplicate the item in the blue action bar.
3) Lastly, if I click on the item itself in the Catalog, the dialog box that opens will have duplicate as third option.
Once duplicated, the new item will appear the first in the list.