On a phone app, and you had to record some videos of yourself answering questions. You had to know a little about general grocery shopping and you had to have watched and learned from the Shipt tutorial you were supposed to watch. They did answer some questions on how to pick produce and some common sense stuff, like picking up the frozen food last and what to do when a product was not available.
If you do most of the shopping for groceries in your home and have common sense, you should do fine. You must also know how to provide customer service and be service minded and respectful of others, otherwise, you may not know how to answer some questions correctly.. and you probably would not be a good candidate for this anyhow.