More information: Setting your scheduler
On the scheduling details page where clients enter their contact and billing information in your online scheduler, you can customize the text on the button they click to book their appointment.
The default text is Schedule Appointment.
Customizing the Schedule Appointment button
The button allows a single line of text with up to 50 characters.
(1) Go to Settings > Scheduler (design)
(2) Click on the Language tab
(3) Next to Customize, click the No button to change it to Yes and enable
(4) Enter your custom text in the Schedule Appointment Button field
(5) Click Save