Yes, you're on the right path, but you'll need to walk it many times.

If you already have a startup idea, or let's be informal and say you have pretty good idea for a website, don't build it first. You'll get frustrated, cursing Javascript for not letting your awesome thoughts flow from your brain to the screen.

Do like the game developers. Make Tetris, then Asteroids, then Arkanoids, then a Pitfall clone. Start it easy.

I would say make a... wow that's old in internet times, make a Guestbook, then a blog system, the add categories, comments, trackback, that stuff. You'll know what it needs to be added, and that clear goal (not to mention the abundance of online resources) will smooth your way.