I found the following site that seems to be awesome!:

User Onboarding and Product Walkthrough Library | Intro.js
https://introjs.com/
Create step-by-step product tours, user onboarding guides easily. Intro.js is a lightweight, open-source user onboarding library. Get started for free!


It allows you to add popup feature introduction to your site, including multi-page demos:
User Onboarding and Product Walkthrough Library | Not Found
https://introjs.com/example/multi-page/index.html
Create step-by-step product tours, user onboarding guides easily. Intro.js is a lightweight, open-source user onboarding library. Get started for free!


The only hard part is getting it to work (which I have yet to do).