Welcome!
Then you'll have to find something to work on. Maybe an open bug? Or do you already have something in mind?
You should be aware that V8 has a large, complex, fast-changing code base. Getting started with it does take some perseverance, and the willingness to follow a steep learning curve. (I don't know what your background is; if you're just looking for some open source project to contribute to in your free time, you might have more fun elsewhere. That said, we would certainly welcome your contributions, and once you're past the first couple of months and have an idea what you're doing, hacking on V8 can definitely be lots of fun too!)