Can prospects cancel appointments since they are not able to login?

A prospect can cancel an appointment if they have the direct link to their appointment in your Console calendar. You can provide this link by using the replacement tag $APPOINTMENT_DIRECT_LINK$ in your appointment confirmation and reminder template(s), in Calendar menu > section 'Notification Templates' > add/edit notification template > insert the tag from the 'Replacement tags' drop-down list in the notification template editor toolbar. The tag is filled with the direct URL of the appointment when the confirmation or reminder is send and the prospect can go to that URL to change the scheduling or cancel the appointment. And you as coach will automatically get an email notification about the cancellation.