I'm all for tech independence. But if you need to be spoon-fed the instructions like this and you don't get what most of it is doing, YOU DON'T WANT TO DO THIS. Best case scenario you'll get locked out of your own stuff or important information.
Yes, you should strive for that, and you start by learning. Contrary to popular belief, you don't need to be a linux ninja to be able to host your own website and calendar.
The stuff mentioned in this article are the bare minimum, and you should want to do it yourself without being spoon fed the steps.
With that aside, this is exactly the kind of guide I would expect a three-letter agency contractor or worker to spread in order to "help you" stay off the grid, then unceremoniously drop a disaster on your head.