How can build a CRM for a training center ?

Hello everyone, For a internship, I was asked by my supervisor to build him a CRM, so he could be able to manage his training center enterprise. The CRM's objective is to be able to assign a teacher to a course, assign a class of students to a planning, etc. My supervisor must also be able to create new profiles (teachers, students,...), create new (virtual) classes, to generate plannings which can be exported in PDF. For the moment, this is all I know. I don't really know where to start so if any of you could give me a hint, I would be very grateful. Thank you for your attention !