Thanks for reaching out! 

 You are welcome to attend any of the public Yocto developers meetings, if nothing else you will meet and hear directly from the core developers. However it's not strictly required. Anyone is free to start contributing. You can work either on items that are already in our Bugzilla, or work on things that are important to you too. If you pick up a task from Bugzilla, it's a good practice to engage on the bugzilla bug and tell them that you want to work on it, so that everyone is aware of it. 

We have a special category of bugs which we mark for NEWCOMER. They are usually non critical items, and often 'simple' so that they are suitable for new developers starting with Yocto. See 

Our contribution process is to send patches onto mailing lists, where they are reviewed/discussed and eventually picked up by the relevant maintainers. You can keep asking questions here, if you need more assistance to send your first contributions!