The PageData part is the place where the Website Editors can modify the page content using the information that was setup in the PageType section.

You will find 2 parts to use.

WYSIWYG

This is a standard WYSIWYG editor found in all normal pages.
One difference is that you can add the information used in the fields described below.
To do this use the fieldname enclosed in curly brackets {}. The fieldname must be in all capitals to be seen as replacable field.
A field named "email" should be added in the content as {EMAIL}.

Fields

The fields here are setup in the PageType editor by the system administrator.
Since the form that is used here is not used by end-users, there are no checks on the content you fill, or on mandatory fields. It is your own responsibility to fill the fields with the correct data.