Know what the call is about

The fields on an event type's booking form. Every event starts with name, email and a few more, and you can add your own on the Booking form tab. Bookers answer them before they confirm.

Short Text, Long Text, Number, Select, MultiSelect, Checkbox Group, Radio Group, Checkbox, Phone, Email, Address, Multiple Emails and URL. Long Text can set a minimum and maximum length, and on a paid event the options of a Select or a group can add to the price.

Mostly. Your name is always required, though you can split it into first and last name. Email, phone, additional notes, guests and the others can be made optional or hidden. You can delete only the questions you added.

Onto the booking: the booker's confirmation page lists them, they're in the host's booking emails, and they're added to the calendar event's description.

Yes. Each question has an identifier, and adding it to the booking link as a URL parameter, like &name=john, fills that question in. You can also lock a question once the link has filled it.

It takes the question off the booking page without deleting it, so you can switch it back on later. If a link fills in a hidden question, the answer still reaches the host, and only the host's emails show it.