If you're wanting to learn Javascript, and you really want to learn, I'd recommend staying away from Jquery. It simplifies a lot of things without really teaching you how they work. Everything that can be done in Jquery can be done without the use of plugins, and you won't have to depend on it for all of your projects. Javascript is fun.

3-4 months ago, I knew nothing about javascript. I found this guide by the great /u/eschatonic (which I see other people linking below, it really is a great guide), and have been making pretty decent progress on my own project since.

If you're programming-minded, that guide should spark something in you. It's super basic, not tough to digest, but it gives really great examples of how javascript works, and how to set up the core of a really basic game. Part 2 even handles saving/loading.

Making a game with unique mechanics is hard. Making an online game is harder. There is nothing wrong with setting your sights on an online RPG with PVP, but it's not the place to start. You can't just go down a double black diamond ski slope before you've learned to pizza and french fry.

Copy a simple game like cookie clicker first, but in your own code. This way you don't have to think about mechanics or design, you can just practice your code and figure out the best way to handle things. You'll probably want to restart 3 or 4 times and use a different programming style. You'll learn a ton by the time you've done that, and you'll feel more confident and knowledgeable about what you're capable of. If you feel like programming is second nature at this point, then start working on your PVP MMO.

Of course, these are all just recommendations. Your learning process could be very different from mine, or programming might just be in your blood. But I think it's generally recommended to start small, then work up.

Best of luck!