What's the difference between "product" , "goods" and "commodity"?
"Commodity" has a special meaning as a raw product that is generally the same from one batch or producer to the next. While you can can buy a pound of a particular brand of pinto beans from the grocery store, pinto beans are traded in the stock market in much larger quantities based on a "commodities" price.
You might hear the phrase "a rare commodity". That kind of twists the meaning to suggest that the thing is special. Patience is a rare (valuable) commodity in teachers.
"Products" and "goods" (in that sense) are fairly interchangeable words. Product has a bit more sense of specificity. Peanut butter is among the goods typically found in grocery stores, Skippy peanut butter is one of the products you might find on the shelf. You're more likely to see "goods" (plural) than a "good".
To make it even simple, in a layperson's language -
Commodities are something used to make goods. And goods go to the end users. For instance, flour is commodity and bread is goods. If I tell you in a very informal way then commodity is a species of molecule/grain or whatever. Whether you buy wheat from place A or B, wheat is wheat.
When it comes to a product, the manufacturers have plenty of options to make that commodity-turned-goods theirs. In short, products have their names/labels and so a different identity. Here, they come out from the general species and get a proper noun!
Also, consider the last two paragraphs of Jolenealaska.
Here is a good article on product vs commodity.
The article Welcome to the Experience Economy by Pine & Gilmore (1998), provides a table in Page 98, which also explains it well.
I hope you find it useful.