Booking consults wordpress plugin

Specifications SW
An online system to book an appointment with Sandra Cavaco (linked to qifang.eu)
Sandra should have the possibility to authorize and/or block specific time slots.
The system should present the time slots for the current month plus 3 additional months.
An existing customer will have a unique code to access the system.
The available time slots should be visible (green color)  in order for the client to select one of them. If the time slot is already taken it will be in red color.
Are the time slots all equal or not? (i.e. One hour) YES
Specific selection for the first appointment (new customer) : data introduction without the possibility to select a time slot. A new customer will be contacted personally.
The customer should introduce the name, the first name, the email and the telephone number. A customer reference code (given after the first appointment) should replace the full data entry. The customer should have the possibility to cancel the appointment until 24 hours before the actual date.
If the appointment was fixed more than 2 months in advance the patient should receive a reminder one week before it. For all the other appointments (less than 2 months) an automatic compulsory reminder 24h before it should be issued.

To reserve an appointment in the Agenda :

Existing patient => insert code => access the booking system

New patient => click here => filling a FORM => click send. As we receive the request, we send a Medical Questionnaire, the references to pay in advance and a customer code to access the booking system.