Laptop Does Not Recognize T-Mobile Internet

Yes, the method described here should work for your older Windows computer. Because of your laptop's age, there is a chance that it will not be able to "see" a WPA2/WPA3 secured network. If that happens, you must use the phone app to downgrade it to WPA/WPA2. The app is downloadable from the Apple App Store or the Android Store.

The Hidden switch is under the Network tab of the phone app. Launch the app, then tap the Network tab at the bottom of the screen. The Hidden slider is at the bottom of the configuration screen, so you will have to scroll down to see it. I leave mine off since hiding a network will not keep a dedicated hacker from using my WiFi.

IMHO, Ethernet is always preferable to wireless, but there are only two Ethernet ports on the back of my TMHI Arcadyan KVD21 5G gateway. I use one to connect to a 5-port, 1 GB switch, which I use to connect one or two devices via Ethernet. The other port is connected directly to an Apple TV. I've also successfully used TP-Link Powerline adapters in my home to extend a wired network to my wife's computer and a TV mounted outside. They work perfectly and are combined with a WiFi range extender that covers a dead spot in one room of our house. For the record, that dead spot existed with Xfinity as well as TMHI.

Good luck with your new service!