You can add themes to change the look and feel. You can add modules to add functionality. But you can also add providers to login using social media or your credentials of your office network.
There are several ways to get what you want:
- Shop till you drop on https://store.dnnsoftware.com/
Note worthy is that the DNN store does not just offer another caroussel or calendar. Several vendors off solutions that allow you to create your own application, even if you are not a dev guru. If that's way over your head, you can still buy a caroussel as well ;-)
- Create your own extensions. More on this can be found on https://dnndocs.com/content/features/extensions/index.html
But it doesn't stop there. If you just want to leverage the users/roles/permissions of DNN but don't want any of the other stuff, you can do that too. DNN has an extensive API to use whatever you need and whenever you need it.