In the Admin UI, under Settings > General Settings, there is a text box able to contain a URL for bookings Terms & Conditions.
The URL could point to a file or to a web page containing T&C.
Through this URL, customers will find T&C during the Booking Details after creating a new booking in the Customer UI.
T&C link appears in the text of the mandatory checkbox to select to proceed with the workflow and view the order summary as shown below.
T&C also appears in the "Order Summary" step of the booking confirmation on the Customer UI