Make Documentation Private
Private documentation isn't accessible to public internet and anonymous users. Only authorized GitHub users with an access to your private repository are able to view the private documentation.
A private repository always published as a private documentation website. We expose a private repository to the public internet with an authorized access only.
Give permissions to users to access the private documentation
In order to give an access to the private documentation you need to provide the users an access to the GitHub repository.
If you are using personal repository, you need to add a user as a collaborator in order provide an access to the documentation website. Please visit Inviting collaborators to a personal repository page for more details.
If you are using GitHub organization repository, you need to provide
Read access to the repository to give the user permissions to access the documentation website. See Repository permission levels for an organization for more details.
Be aware that all members of the organization can access all organization's documentation websites by default.