Job interview at save on foods?

Quitting my new job hopefully if i get this job. I have an interview in the morning at 10:30. I really need this job cause 2 4 hour shifts a week arent cutting it for me. i wanna get paid more and work more hours. I have trouble with questions like "can you tell me what you would do in this situatuon" questions. or "when was the last time you helped someone without asking" like i feel like some of the job interviews i've had i would have gotten the job if i knew how to answer the questions and not make up some words to try and make it sound professional. How would you recommend prepping for the interview and save on?