Hi,

You can create a field only Label. I want use this field for title of a group

You can use HTML delimiter field type, docs at http://docs.easy-profile.com/index.php/article/html-delimiter-field-type

And when i delete any fields. It only delete on backend, it don't delete in database ( jsn_fields, jsn_users)

When you delete a field it goes on the Trash, you need to remove also from trash. To see Trashed items you can filter for "Trashed" from sidebar (see screenshot).
This system is the same of Joomla core component (also Joomla articles).