How to recreate this?

Hi there, I'm currently making a website in Elementor and I encountered this:

https://www.digitalsilk.com/web-design/custom-website-design/

Basically when you scroll a bit down, next to the contact form there are headings and when you hover on them paragraphs appear. I coded that in CSS and it wasn't too hard but how do I make the same effect like on that website?

While my current try only shows paragraphs when hovered on, I want the first one to be active like on that website. And when you hover on any of them, I need them to stay active.

The blue line on the side would also be great but yeah, I'm currently stuck.

Thanks in advance!