Drupal 8 has a core module built in to help with this call Tour which is built on the jQuery Joyride plugin.
If the website is built with bootstrap you might try the bootstraptour plugin git show your users all the features or guide them through some steps.
If your sites is not using a framework which offers a tour api you can build one with Joyride easily enough.
You might also consider a not-so-obvious approach to teaching users your features. StackExchange, and many sites, use a badge system to reward users for doing more things on the site. This coupled with the "Next Reward" system helps to teach users how to use the site and gives them more insight into all the tools the site offers without expecting the user to read endless doc pages and watch boring videos.