Adding functionalities and capabilities

How do we add more functionalities and capabilities to our websites?

Using plugins. They are software you install into your website to add or extend functionalities.

A basic WordPress website comes with posts, pages, a media uploader, and a simple customizer that lets you change some appearance settings in your website. 

Plugins may add e-commerce features to your website, a fancy user profile viewer, a course creator, or even further customization options for your themes. There are very few limitations to what they can do.