How to properly design an object-oriented model for the job?

Question

OOP

Please help me to correctly draw up a class interaction model, i.e. : which classes should be present, their relationship, class structure, etc. I can not quite figure out how to build this structure correctly. The task is performed in C#. Thank you.

"The registry provides data on the availability of doctors and the schedule of patients. Patients can make an appointment with a doctor if there is free time in the doctor's schedule. The registry maintains cards for visiting patients in the hospital, which record the time of visiting the doctor, the diagnosis and the doctor who made it. "

Answer 1

Entities (classes): patient, registry, card, schedule, doctor, diagnosis.
Actions (methods):
The patient applies to the registry.
The Registrar sets the time.
The patient comes to the appointment.
The doctor makes a diagnosis and enters into the card