Contribute through forks and upstream repositories

In many open-source projects you cannot create branches directly in the main repository. A fork gives your account its own GitHub repository where you can push changes and propose them back.

A fork is a GitHub-hosted copy relationship used for independent development and contributions. Your clone may use origin for your fork and another remote—commonly upstream—for the original project.

Before contributing, read CONTRIBUTING.md, code-of-conduct and test instructions. Keep each PR focused, sync with upstream when needed and avoid mixing unrelated personal changes.

Run this in a disposable practice repository unless the lesson explicitly says otherwise.

git remote -v
git remote add upstream https://github.com/ORIGINAL_OWNER/REPO.git
git fetch upstream
git switch main
git merge --ff-only upstream/main

The exact sync strategy can vary. The key concept is that your fork and the original repository are separate remotes with separate branch states.

Your task: Draw a four-node collaboration map: original GitHub repo, your fork, your local clone, and your feature branch. Label origin and upstream.

Do not assume every project wants the same contribution style. Follow its documented branch, test, signing and PR requirements.

Contribute through forks and upstream repositories is complete when you can explain the state being changed before you run the command, not merely repeat the syntax.

Read further: official supporting documentation.