No, those are different. They are describing a femtocell. I still have one site with a T-Mobile one. It basically VPN’s to T-Mobile’s network core through the cable ISP, uses GPS to check its location for licensed spectrum, and then broadcasts its own LTE signal. It does not boost/repeat the signal of a nearby tower, it runs its own.
Private 5G networks usually need internal eSIM cards, you can't just let public devices roam into the private 5G net.
Benefits of 5G over WiFi: much better roaming between APs, higher distances, and better congestion management if there are hundreds of devices connected to a cell.
For most use cases WiFi should be the better solution. VoWiFi works well for calls. Should be enough for home and office use.