Changing product type for products in Craft Commerce
I personally think mucking with the schema here is bound to get you in trouble.  Very easy to miss something.

If you don't have much data in yet, simply start again, and chalk it down to learning/experience.  (Personally I think there should be a 'Start This Way' page in the Commerce docs that  emphasises Data Modelling for product types is where you should begin!).

If you do have a lot of data in, best to export &amp; then re-import your data using e.g. FeedMe - https://sgroup.com.au/plugins/feedme/getting-started/introduction

(You will need the Pro version which support Products)