There are so many ways to get involved. Start with the libraries you are already using, and find them on Github. Take a look at the open issues, try to reproduce the problems, and report your findings. Read through the docs, and look for things that can be improved. Browse through the list of (closed) pull requests to see what kind of changes get accepted. Get used to reading the source code!

Hi Romario,
If you are interested in contributing to Elixir itself, I just wrote a guide about that.
How to Contribute to Elixir: A Step-by-Step Guide

Also, hang out in the Elixir Slack and see what kinds of questions people have. Try to answer them yourself using the docs and source code. Sometimes people’s questions or comments will give you an idea about how to improve the library they are asking about.

Building on that, docs are really a great place to start. I’m a huge fan of doctesting so whenever I read docs, especially core elixir, and wished there were doctests I make a mental not of PRing those. Small, effective, helps lots of people and maintainers appreciate them. Most of my elixir-lang PRs have been of that kind

Also we have the missing libs thread setup where the community can add ideas for new libraries that are currently not available in the elixir ecosystem.