I explored a similar idea after college as a way to improve textbooks. I haven't done any maintenance in years, but the demo is still online: https://www.okeebo.com/demo/
I found that it was a lot of extra work for authors and they weren't interested.
Since Google search is most likely discovering the AMP page via the <link rel="amphtml"> tag, they really should just use that URL. The Google servers do add a couple minor things beyond being a distributed cache though. First, there's swipe navigation to other articles if the link was located in the top carousel in search results. Second, if you are on a laptop, the Google servers will redirect you to the full version rather than use the AMP cache.
Unfortunately, you really do need to test on all the browsers. That being said, you can have a main browser you develop in and once you finish certain features, do quick tests to see if the other browsers behave the same.
I use Firefox as my main development browser because it doesn't cache files saved on the local disk. Chrome does cache locally saved files, so you need to remember to the clear the cache (Ctrl + F5) after making any changes to your code. This is surprisingly easy to forget and can lead to some frustrating moments.
I do prefer Chrome's built-in console, so I'll often switch to Chrome if I'm going to use the console a lot.
Finally, Opera has a sweet Remote Debugger that's nice for doing client side development for mobile devices.
There's already been great advice about continuing your education and putting together a portfolio, so I'm going to address your question from a different angle.
Problem solving is a big part of programming, and it's a skill that can be used outside of writing code. Do you actually need money to get those things you want? Or can you think of a creative solution that costs less or nothing? Note, I'm not advising you do something illegal that could get you in serious trouble. I'm just reminding you that hacking doesn't always involve a computer.
Perhaps you'll realize that money isn't your main goal, and you really just want to work on more projects. In that case, there are plenty of open source projects you could try.
I found that it was a lot of extra work for authors and they weren't interested.