Really would need to see what the data was and get an understanding of what you are trying to do.
But generally you would alias the fields, you do not want to link on, leaving just one field linking two of the tables Some like
[Sales ] :
Customer ID AS Sales.CustomerID
OrderID AS Product.OrderID
Sales ID AS Product.SalesID.
Would get rifd of your synthetic keys. Byt not knowing the Data is maybe you need to make concatenated keys to get the correct joins.