Can customers book online?
Yes, through your booking page.
Your booking page link is in Setup → Company and online booking under Your booking page. Put it on your website or send it to customers.
In Setup → Services and prices, mark each service Online (customers can book it) or Office only. Customers choose a service, enter their address, pick a free time and create a PIN.
Online bookings arrive as requests on the calendar. Open one and press Confirm booking.