Newbie Prediction Model

Question

Hi
Newbie Question Hope you can help.

I have sales data where each client is listed as "industry class". I want to create 2 types of "predictions" which products similar clients should purchase based on their "industry class. And also what products should be purchased based on time lapsed between specific item purchases.

Basically my Table has 5 columns Item, Item Description ,Industry code, Purchase Date, Customer Number

and the model asks for 3 columns to work with :

User Column I would assume would be the CustomerNumber

but then what's the difference between "predict" and "item"?

Thanks for the input :)

mrrcomp