It sounds like you’ve been head-hunted, but it’s very unusual that they wouldn’t provide you with a full brief and job description. Personally I would contact the person who has contacted you, and ask for a full job description so that you can better understand the role which you might be applying for. That’s not an unreasonable or inappropriate request.
It is very unlikely that the person who has contacted you would describe an induction or 2.5 hour training session as an interview. Instead it might be an interview/introduction to the company. The only other thing you can do is to continue with your research online or maybe ring the company and see if you can speak to someone actually working in the department you are proposed to be.
Good luck!