Predicting products to be sold in a store - problem formulation
To answer your question, in that dataset the first thing to do is to determine the types of products in that product sold column or whatever. If you have like 3 or more different kinds of products to be sold. Then you can rename those types and use a classifier algorithm to make your prediction. So the product sold will serve as your target variable and other closely correlated variables will now serve as your predicting variables.
So to add to the above, you want to predict the number of products to be purchased by a customer, then I suggest you look out for good multi-target regression models.