Hello, I just purchased my first house and it has a cabinet of spaghetti in the office and I don’t know what it’s for or how to use it. But it does look expensive so if I can make it useful to me then I’d like to!
What you're looking for is a MoCA network. It won't be cheap, but it is possible. You'll need an adapter in every room you want wired internet, and high quality splitters. Setting up a Powerline network might be cheaper. But quality of that will be dependent on the quality of your electrical system.