This template includes the basic Ultimate Member plugin, which gives you a host of resources for managing site users, if you need that functionality. Be sure to read the documentation for the plugin, and have a privacy policy that is reviewed by legal before storing any user information on your WordPress site. But the plugin does make it easy for members to manage their privacy settings.
The main use we have seen with this plugin at AHA is to secure certain pages to only users with an account who are logged in. It can even hide and show menu items based on if the user is logged in or not.
These are the pages the plugin creates by default. But in most cases at AHA, we have seen just a basic implementation, with possibly a custom registration and login page, but all the other pages are not used.