Welcome to the community forums.
The best way to start is to ask and try to help into the forums. There aren't better or worse questions here. ;-)
You'll find a information on StackExchange too and you can start diving into the http://devdocs.magento.com/
Another recomendation could be to be aware of Magento issues on Github: https://github.com/magento/magento2/issues (if you are technical, of course).
Also, you should read this post: https://community.magento.com/t5/Welcome-to-the-Magento-Community/Start-here-and-hello-from-me/m-p/5... (in particular the guidelines)
Fianlly, you'll need to get your hands dirty with the platform.