Tip: If you ever need to do this on a public GitHub repository you can use "gitingest".
This will open a website that creates a copy of all the file contents of the repo (code, docs, ...) It's a great tool to use when using new/obscure code with LLMs in my opinion.
The UX is so just easy and great, change the URL from <https://github.com/user_name/repo_name> to <https://gitingest.com/user_name/repo_name>
//edit: fixed URLs