I use newsdemon as my primary provider with a few block accounts as backups.
I would personally recommend sabnzbd as the downloader paired with sonarr and radarr to handle searching for TV and movies specifically. These are all web apps but they can be run on Windows but also could be running on something as simple as the raspberry pi and then remotely accessed from another computer in your network.
You will also need a indexer, popular recommend ones are nzbgeek or dognzb. Most of these charge either a yearly or a lifetime sub fee but take that with a grain of salt, they often take it away.
Looking for good USENET primer
I used to spend a lot of time on news:// protocol back in the 90s, but haven’t touched it for good 20 years or so....