Duplicating a repository
Before you can duplicate a repository and push to your new copy, or mirror, of the repository, you must create the new repository on GitHub. In these examples, exampleuser/new-repository or exampleuser/mirrored are the mirrors. Create a bare clone of the repository. $ git clone --bare https://github.com/exampleuser/old-repository.git Mirror-push to the new repository.
https://docs.github.com/en/github/creating-cloning-and-archiving-repositories/creating-a-repository-on-github/duplicating-a-repository
Seonglae Cho