Accessing Global Configuration Information in Joomla
Like user information, accessing global configuration of Joomla (like site name, from name) is a very simple process. You can use getConfig() method of Factory class in any part of the Joomla extension or template.
$config = Factory::getConfig();
For example, site name stored in global configuration can be retrieved as
$config->get('sitename')
Similarly, from name can be retrieved as
$config->get('fromname')
You can check configuration.php file stored in root Joomla folder for all the global information that can be accessed in this way.