Only able to add two fields?

Hello.
No, there is no limitations to the number of adding new fields in the Booking Calendar Free version. You can add as many fields as you need.
Please watch more about this here: https://youtu.be/NR5pdYVkLhI?t=126

If you have some issue with adding new fields, please contact support @ wpbookingcalendar.com with screenshots of your issue and link to your page.
Thank you.

Thank your for the quick response.

A followup question, how do I enter the different facilities that are available to book?

Hello.
In the Booking Calendar Free version exist only one default booking resource (calendar). But you can activate to set all days as available or set available all pending bookings at the Booking > Settings General page in Advanced section. And configure seletion of facilities as option in selctbox in the booking form.

If you need to have real independent calendars – booking resources, then the ability to have independent calendars possible in any paid versions of Booking Calendar. Check more here https://wpbookingcalendar.com/overview/#booking-resources

You can watch video overview about this feature here https://wpbookingcalendar.com/help/multiple-calendars-video-overview-of-booking-resources-in-booking-calendar/

Please read firstly the general instruction about usage of paid versions of Booking Calendar: https://wpbookingcalendar.com/faq/general-usage-instruction/

You can create the different booking resources (your properties or services – unique calendars) at the Booking > Resources page and then you be able to insert booking forms for each of your booking resources into the posts or pages. Please read more how to insert and configure the booking shortcode into the post or page here https://wpbookingcalendar.com/help/inserting-booking-form/
You can test Booking Calendar live demos at this page https://wpbookingcalendar.com/demo/ to be sure in functionality and do not have misunderstanding.
Kind Regards.