Sometime ago I finished Codecademy's Web Fundamentals. I learned enough to understand what's going behind the scene but not enough to start hacking on my own. S

Sometime ago I finished Codecademy's Web Fundamentals. I learned enough to understand what's going behind the scene but not enough to start hacking on my own. Since then I have started learning Python, also on Codecademy. There's Java for Android. And I would also like to learn C++/QML to hack my Arch Linux/KDE box. Is it common for programmers to be proficient(reasonably well) and also be able to work on multiple projects requiring multiple languages at the same time? Or do most folks learn many things but tend to work with one language on one project.