Re: Not sure where to go
First you have to understand the paradigm shift from the "old school" (server-side) frameworks like RoR, Django, Laravel or ASP.NET MVC and the "newer" (client-side) frameworks. Maybe read up on Fat Clients vs. Thin Clients. That said, the hype train already moved on (the MEAN stack appeared in 2013!) towards other usele.. ehem, other technologies, but you can safely ignore that stuff.
My personal recommendation is to learn one server-side framework first - doesn't matter which one, just take 6 month and kick off a project. Afterwards you might want to look into Vue. If you understood Vue and are still curious you can take the deep dive into React. But be aware that (unlike Vue) React is not only a complete ecosystem with many different components but introduced whole new methodologies. Stuff like Flux or JSX breaks with a lot of classical web dev paradigms (i.e. keeping code and formating separated).