I went for an interview but they never let me know whether I got the job or not. I prepared for the interview but they didn't ask me anything except when can I start and whether I have a car to get to work.

Very simple. A quick chat with the agency about role expectations, followed by an in-person chat which was more of the same really. "Can you lift X amount?" "Can you work X amount of days/hours?" "What experience do you have?" are the sort of questions to expect.