Get next appointment date using DateAdd and store in variable

    Dim NextAppointment As Date

    NextAppointment = DateAdd("ww", 1, AppointmentDate)

Use an INSERT INTO statement to add the appointment to the Appointment Table.

Ewa, Richard covers this in the Date Seminar.
Access DateTime Seminar

Thank you for your answers.
Have started the Access Date Seminar, have managed 3 lessons so far.
Is it possible to start the calendar without selecting DatePickerF first?
Because if one misses this first step, a message will appear "Enter parameter value", even if a value is written, it will be a new error message. The easiest way is to click Cancel, unfortunately this has to be done a number of times before the box closes. Would like to avoid this procedure if possible, without too much difficult programming,

You would have a Form with a button to open DatePickerF or set it as the Display Form..

Only allow users to open the Calendar from that form.