You don't know JS free open source book series is probably one of the best resources too. It explains how JS works, other than explaining how to program it in a nice way.
I think that if someone understand well how a programming language works, then he should know how to program it in the proper way, no? :)
If you were looking for a de facto direct replacement to MS SQL Server and just didn't want to have to "think" much about anything, the obvious choice is PostgreSQL. It is one of the world's most powerful, mature and respected database platforms. It is insanely fast, scales insanely big, is supported on the most enterprise style deployments, does relational the same way that MS SQL Server does and so forth. It is the most direct competitor. And you have loads of top end support options for it. So if you want a safe "starting point", start there. It's hard to go really wrong. But best to do an evaluation of needs as there are just so many great options
That's a start. So that still leaves you with dozens of language choices like Perl, Python, F#, Ruby and more. But 99% of the time the site that is ASP.NET will be built with C# or VB.NET. So you'll need to look at the code to determine which one, but C# looks like Java and VB.NET looks like it was written by a little kid, so they are pretty easy to tell apart ;) No seriously, they look nothing alike, so it's normally super easy to tell.
I don't think it really matters that they use Chromium core, it doesn't explain such an odd GUI change that went in the opposite direction, and I wasn't the only person who noticed either. If two sites use WordPress and one makes a change to the style of an element, then another does a week later, the fact they both use WordPress really doesn't matter.
I do not use VS Code, but I have it installed to play with on Linux Mint. For me, Atom, which Code is based on, makes more sense and I use it all of the time. Atom does pretty much any language that you want and is older (so I was using it long before Code came about) and has gobs of resources. I come from a background of just using vi for everything, so Atom is a pretty big leap forward.