I have a Ubuntu machine that is not allowed to be connected to the network and it is locally connected to a Windows machine. Due to security requirements, this machine is disallowed from network connectivity. I want to set up a local repository on the machine so that if I ever need a package I can simply use the apt package manager to install my packages. I'm having difficulty finding relevant resources on how to setup an Ubuntu repository that don't assume you have apt/internet activity. (The classic chicken-and-egg problem.)
In this case, my offline machine has a little help, i.e., a network-connected Windows machine that can download all the software it requires, except no instructions explain how to set up an Ubuntu repository that isn't already part of the Ubuntu ecosystem.
I have set up RHEL repositories in this manner because they use the ISO install disks as their repositories. That is straightforward once you understand how to mount the ISO onto the file system. In the case of Ubuntu, most directions have tools that only a network-connected Ubuntu machine with apt can use.
How can someone set up an Ubuntu repo that has no access to network resources from the get-go?