IMO, after you've become familiar with the mechanics of the language
you should start looking into
principles. Read up on design principles, problem solving techniques, refactoring,
testing, and other things you have to do as a developer. Developers don't just have to write code, they also have to analyze, design, organize, test, collaborate, etc. If you want to get a good start on a career in software development, it's best that you're at least aware of the other things you have to do besides write code and deal with technology. If you search these forums for book recommendations, you'll find quite a few good ones where you can start learning more holistically.