TREND

I'm new to 3d modeling and I am trying to create custom props for CS:GO and I am not sure how to import props with more than one material.. for example, I'm making a grocery store and I want to make a shelf with cereal boxes on it and I don't know if I need to combine the materials somehow or just make vtf/vmf file for each and every texture even if it's for one prop which I've tried and it didn't work but could be doing it wrong.