Thank you for your interest in contributing to Rust! There are many ways to contribute and we appreciate all of them.
The best way to get started is by asking for help in the #new members Zulip stream. We have lots of docs below of how to get started on your own, but the Zulip stream is the best place to ask for help.
Documentation for contributing to the compiler or tooling is located in the Guide to Rustc Development, commonly known as the rustc-dev-guide. Documentation for the standard library in the Standard library developers Guide, commonly known as the std-dev-guide.
The rustc-dev-guide is meant to help document how rustc –the Rust compiler– works, as well as to help new contributors get involved in rustc development. It is recommend to read and understand the rustc-dev-guide before making a contribution. This guide talks about the different bots in the Rust ecosystem, the Rust development tools, bootstrapping, the compiler architecture, source code representation, and more.
There are many ways you can get help when you're stuck. Rust has many platforms for this: internals, rust-zulip, and rust-discord. It is recommended to ask for help on the rust-zulip, but any of these platforms are a great way to seek help and even find a mentor! You can learn more about asking questions and getting help in the Asking Questions chapter of the rustc-dev-guide.