So ive decided to create video games and want to start by making a browser based game. I am currently learning Java and HTML5. I was wondering if this is all i needed to learn how to do in order to create the game.

Java or Javascript? Yeah that's all that's really necessary. But yeah you can easily make a game with just HTML5's canvas and Javascript. Or if you meant Java then yes, that has an applet you can use with many ways to make a game. Anything more would depends on the game and your requirements. You left your question kind of open ended.

You may also want to take a look at CSS3 and some of the cool things that you can do.
You also need to be very aware of the fact that this is a relatively new, up and coming thing - so there are still challenges like: audio, browser compatibility, and input (gamepad), etc.

A browser that supports HTML5 (Chrome is a good choice) and a text editor are all you NEED.

It's nice to also have:

• A decent image editing application (I like paint.net. It's free of charge.)
  
• A good debugger (Chrome's got this built-in)
  
• The internet. You'll be doing a lot of search for information on JavaScript and the Canvas programming interface.
  
• Example code. I think someone on this site has written a tutorial on HTML5 and Canvas game programming, but I don't remember who or how to find the tutorials. They could be in the tutorials section of gdnet, but I didn't look.
  
• A friend who knows how to do this sort of thing already.
  
• An idea for a simple game you want to create. Don't try to do World of Warcraft as your first project. Don't even try to do Zelda as your first project. Something like Whac-a-mole would be a good start. You can start with very primitive graphics, the AI is simple (Is it time to pop another mole out?), mouse interaction, keeping score, etc.
  

If you're planning to learn C#, you can also use Silverlight. With its extensive library, it may be quite useful for developing more complex projects.

If looking for some easy sample source code... you can also look at my page, where I have a sample pac-steve game that I used to teach the into web programming course at my school. If I recall right I used JavaScript prototypes so it won't run in most default mobile browsers but the prototypes can be removed fairly easy to make it purely procedural. Biggest problem to watch out for as already mentioned are things like timing... there are no high-resolution timers and it is a challenge to get most mobile browser games to perform equally on different browsers running on different systems. Sound is also a challenge; back when I wrote pac-steve, the audio was so choppy I had to remove it (don't know how it is now a year later though).

Pac-Steve