Thanks for taking the first step in contributing to Brave! We have a few places for you to get started, depending on your experience and interest.
If you have never participated in an open source software community, start by trying to help others. Join new threads and see if you can replicate the issues other users report.
@Jacalz is the undisputed champion in this regard and would be a great person to talk to about how to get started.
Testing Brave in all of its forms and across different systems is always an area that needs help. We have systematic regression test runs you can participate in or you can do more exploratory testing.
@alex @suguru and @sriram are good people to check in with when you want to get started here.
We have three major platforms for development, so you will have to what resources and interest you have before starting.
@clifton will be able to point you in the right direction.
@joel is our dev lead for Apple mobile devices.
@Serg is our dev lead for Android mobile devices.
@brad runs all things design.
If you are interested in usability testing or design research in particular, @alex can get you started.