If you'd like to duplicate your product when creating new ones, then here's a super-quick video showing you how. Written instructions below.
*Please note that if you're selling physical products that have variants, you can add variants when adding your physical product. Just find the "Add Variant" section on the edit product page. Note variants are only possible with physical products right now.
How to duplicate:
Create at least one product
On your dashboard, go to Products > Products Listing in the top menu
Find the product you want to duplicate and click the three dots on the right side and click Edit.
One the product edit page, click More Actions>Duplicate.