The create-edit genealogy allows to to either manually start a new genealogy, or edit the main information for an existing genealogy.
The form holds a number of fields, that will be explained below:
If you import a gedcom file, most of those fields will be derived from the information in the gedcom file.
If you create a new genealogy without an existing gedcom file, you shouldn't be too worried about many of the fields.

//name of the genealogy
title : you must provide a 'title' since that will be the name under which anyone can view your genealogy.

//gedcom file specific (only used if you import a gedcom file)
sour : the source of application that created the genealogy (for instance 'Family Tree Maker')
sourvers : the version of the application
sourcorp : the name of the company that created the application
sourcorpwww : the website of that company
dest : the destination of the ouput file from the gedcom export in your application
gedcvers : the version of the gedcom format used in the gedcom file

//administrator or user who created the genealogy (not required, purely for information)
name : your name
address : your address
cont : additional address information
email : your email address
phone : your phone number