Want to start building clean responsive sites, but don't know how to start

I look at the templates from this website and I think, wow, these are beautiful, simple, and clean. But, then I hit the developer’s version of a writer’s block because I don’t know where to even begin to make websites like this.

Do I start with just writing html to build the content, then use CSS to arrange the content into neat boxes, and then add javascript for animations and functionality?

Or do I download the source code and copy it, while understanding what each line of code represents and changing what is needed for my project?

I’m just super bad at coming up with anything on my own, and I always need some sort of reference to get started, but I feel like its cheating just looking at the source code when building websites.

Just do it like a project header, nav, section1. Here’s a video. This author did another one that produced backgrounds more like those in the website, but this one will do to get you started. You can use figma instead. It’s free.