The documentation is confusing. The official debian wiki does have a link to the page. That repository is maintained by Nvidia for datacenter usage but it works for desktop drivers as well.
The page below has a tool for how to add the Nvidia repo on different distros. It also has the option to set up your own local repo. Do not use the install script named "runfile", it could brick your distro install. Only install the nvidia driver through the distro package manager.