You can always bet on JavaScript, you say that you want to be a full-stack developer, so you will never go wrong with that. For a path I would recommend choosing a project you want to build, as many programmers say - "Everything will eventually be built in JavaScript" - choose a project and try to jump right into it, see as many references as possible, watch youtube videos, but most imporantly!! Build something you are passionate about and have fun! :)