How I should continue my learning journey?

Hi
Like most of programmers I started learning front end
I watched colt Steele course, web developer bootcamp.
I learned HTML and CSS, try one of the css framework and completed some of https://www.frontendmentor.io/ challenges.
After that I started learning JavaScript, I tried other resource like https://javascript.info/ and I got deeper in JS.
Today I checked colt course and I found out I learned JS more than what Colt taught in his course and I kinda like what I learned
Here is when things get messy!
I always heard from professionals that you should learn one languages then start another one or don't try to learn more than one language at the same specially if you are beginner
In Colt web developer bootcamp, he teaches a bit about JS a bit about React and Angular, a bit about node.js, about about PHP and...
I asked myself how I should continue my learning journey?
I should stick to learn JS to an expert level or I should stick to colt course so I could learn a bit about more than one language?
I want to learn programming as a second career so I could make some money out of it so I want to know what I should do to achieve this goal sooner