Various pages are getting spread out, so let's see if I can unify them. Also, I'll try to unify various thoughts on the subject.
As you're learning, keep in mind that it's not necessarily hard to get high Google rankings, as I've found. Consider making your own lessons or courses or examples. I will very likely publish them for you (in your name or an alias of your choosing), or, better yet, help you through creating your own web site. Domain names cost about $15 a year (not month). I'd probably give you web space, but if you wanted your own it's about $5 / month.
I have found the hard way that the internet lacks good examples for all sorts of stuff. There is probably money to be made by attracting people to your site.
I tend to follow a URL / path format such that pages created in July, 2020 go in t/20/07. From 2010 - 2019, the format was t/0, t/1/, ..., t/9/. Note that I got caught up in my own version of Y2K. Back in 2010, I thought, "Oh, my professional life will be vastly different in 2020. My little old web site won't matter anymore, or I'll have totally overhauled it. Ha! The joke is on me.
The point being that you can manually crawl my site starting with /t. That is, generally you can. I'll let you look up Apache's Index / Indexes rules. :)
This page is _gu as in "grand unified" as in the attempt at a grand unified field theory in physics.