Before your interview, you should study a few of the most common drinks a barista will be asked to make. It can be hit or miss if an interviewer will ask direct questions like this, but it's best to come prepared anyways. Knowing these basic drinks will show you are either a coffee fan, or you care enough about the interview to come ready beforehand.
"The difference in these drinks may be the ingredients, or something as simple as how they are layered. For instance, a latte macchiato is steamed milk, then espresso, then milk foam. A cappuccino has espresso, then steamed milk, and then milk foam. The same ingredients, just a different order! To make a macchiato, take your espresso and top it off with a small amount of steamed milk."
"I understand, as a coffee lover, that there are small but significant differences in these drinks. It takes a lot of work to learn them all; however, I can say with confidence that I know how to prepare the majority of drinks on your menu. When it comes to a macchiato versus a latte macchiato, and a cappuccino, it's primarily the order of how the ingredients are layered in the cup. A macchiato is the simplest, just espresso and a small amount of steamed milk. A latte macchiato holds steamed milk first, and then espresso topped with milk foam. Where a cappuccino starts with espresso, topped with steamed milk, then milk foam."