There's a lot of articles about supply based usage vs demand based energy production on that website. The idea that it turns off every now and then is sort of part of the authors' intention of showing "we can live with some outages".
Interesting read. Even though you had only medium amount of trouble, it was enough to once again convince me my earlier decision to not do this is the right one. My Hetzner instance had an extended outage for the first time in its livetime this year, and after that I considered moving to CDN. However, due to the little things you list here and your bottom line of " For a blog my size it’s most likely overkill", I decided to just run a Hetzner instance without CDN.
Reading https://solar.lowtechmagazine.com/about/ made me reconsider if 24/7 uptime with 99.9999% SLA is really that important. It's a poster on the internet. What does it matter if the poster occasionally falls off?
First: Great that you're motivated to learn this stuff! When it comes to programmers I've worked with, usually the best ones are those who learned programming to do something for FOSS or wanted to create a thing themselves.
Second: If you're planning on university, an IT degree doesn't hurt. You'll learn a lot of stuff that -can- be useful. At the same time you don't need one.
Practically though, start learning a programming language that is relevant to one of the projects you care about. If you want to learn programming in general, start with Python for a very easy introduction to the basics. If you want to learn more about how computer work (you should), learn C. For learning programming, I recommend books instead of websites, especially if you learn a system level language like C.
Once you've learned a bit of programming - apply it! Go through the bugtracker of the software you use, and find a bug someone has already solved. Read what the bug was about, then read what changes were made and understand why that fixed the bug. The most important practical skills for a programmer are reading other people's code (especially for what you want to do) and debugging. Remember that the most common question a programmer asks is not "how do I do this" but "how does this work?" Another common one is: "WHY does this work?"
But you may also be able to contribute without programming. Many of the software you use requires people who understand how the operating system works to configure it, package the software, and help others like you to solve problems. All of this can be done without much understanding of programming if you spend some time to get familiar with the manual of your software and how the software interfaces with your operating system.
Ah, sorry for the confusion - that server's been out of commission for a few years already.