Where to actually find open source projects and how to approach them.

People talk about contributing to open source. And I would like to. But I am not sure how to find good open source projects which need help. And if I did find one, I am not sure how to start https://trackeasy.fun/usps/.

Does anyone know a good open source python repo? If you had to contribute to it for the first time, what are a few things you would do step by step? I assume you need to fork the repository, make a branch, do something, and then see if the owner likes your changes?

Is there a website which people use to find a list of open source projects?

Thanks guys.