If an applicant wants you to book a viewing on their behalf due to any reason, this button just makes it way too simple for you to do that! You can schedule a viewing using the viewings tab or the calendar tab on the navigation toolbar.
Once you select Book a viewing on any of those tabs, a pop-up appears asking for the necessary details regarding booking the viewing and about the applicant.
These bookings, once confirmed, can then be found in the viewings tab, list of upcoming viewings on the management view of the dashboard and the calendar. This will automatically send an email to the applicant who requested the viewing.
Here is a link to a tutorial on how to enclosed for your further reference-
https://loom.com/share/0adc82abccce45f28e4e3f775ae03bc3