Auto Center Interview

I'm a 17 year old in high school and got a call from the hiring manager about a service writer position I applied for earlier this week. I have an interview scheduled for tomorrow, but I'm not sure about my chances considering my availability runs from 3PM-closing on weekdays and full-time on weekends, + I have no previous job experience.

What are my genuine chances, and what should I prepare for when it comes to the interview?