I just found out about The Odin Project, a self-paced online course to learn full stack web development. There are two paths: one is Ruby on Rails and the other is full JavaScript and nodejs. I am leaning more towards Ruby but I wanted to get some more opinions from folks in the field.
To add on to the other top comment right now, it’s not like learning a spoken language. Once you know one, you can pick up another similar language without too much bother. Or should be able to, if you’re not crap.
As for what employers want to see, that’s something I’m less qualified to tell you.