Javascript would be a good way to go because you can build the frontend and backend with a js tech stack. But node can be tricky.

Personally, I ended up going the Ruby and Ruby on Rails route (I'm primarily a designer and frontend developer). Maybe this will help, I started a list of resources for people to get started with Ruby. Would love to know if you find it interesting and useful:

https://github.com/heyspacetime/awesome-rails-education