Query regarding to start contribution

Hey! I am new to open source and want to contribute to processing foundation. Please guide me where to start from. Also please guide me which repository to start from. I would like to work upon Javascript.

https://github.com/processing/p5.js/tree/master/contributor_docs has a introduction
to contribute to p5.js core

just asking / it could help to get the PRO’s to contact you…

I haven’t contributed to processing yet. I have to start on that.