When I first got into programming, I knew exactly what I wanted to achieve. I wanted to make video games. So I read up on game development, and it became apparent that C++ was the way to go. This was back in the 1990's, and tech such as Unity or Unreal Engine was a very long way off. So I began trying to teach myself C++.
But every day, I see people ask "what language should I learn?" My answer - it all depends.
That may seem like a bit of a cop-out, but you should learn whatever language is relevant to what you want to achieve.
If you're just starting out in Web Development, then HTML, CSS, and Vanilla JS are pretty much essential. From there, it's all circumstantial. If you want to work for a FANG company, learn the tech they use. Look for job postings and find out what they want from their developers, and learn that tech. If you want to learn something because everyone else is, then jump on that bandwagon and get good at it. If you want to learn something because it's a challenge, then go for it.
I learned Angular because the job I had said they used it. As it happened, they ended up using Node, but that's a different story. I learned some Perl because the only other guy at work who knew it left the company, and no-one else wanted to. I learned Java because I had to build a Mobile app for Uni. I learned PHP because I wanted to make dynamic, data-driven websites - it's the same reason I'm currently learning Ruby.
So, whenever I'm asked "what language should I learn?", I always reply with "what do you want to achieve?" And once they know the answer to that, the rest just falls into place.