Help setting up Stock Sycn with Shopify

I am setting up Stock Sync for the first time integrated from a supplier to my Shopify store. At this time I need help understanding how to map the fields and there are no help articles on this topic that are clear enough to understand how fields are added. There are a lot more fields from the supplier than Stock Sync is showing but you can add more fields. The question is do you create fields from the supplier or fields that match Shopify?

See attached supplier sheet. And screenshot of what Stock


Do you know how to set up StockSync? Show me example.