How to Edit the Full Joomla user Page

Galileo,
All of the text on that page can be found in language files, so you shouldn't need to modify the template just for text changes.

For better styling, you can either add CSS to your template file to re-arrange/shrink things as necessary, or modify the output altogether. The file that generates that page is:
/components/com_jfbconnect/views/loginregister/tmpl/default.php
We recommend copying that file to:
/templates/<YOUR_TEMPLATE>/html/com_jfbconnect/loginregister/default.php (creating the directory if it doesn't exist)
That will create a template override so that any changes you make won't be overrwritten on upgrade, and will also leave the original intact in case you make a mistake.

Hope that helps, but if you have any specific questions, just let us know.

Thanks,
Alex