Ubuntu as Wifi AP

Let say, we have a ubuntu device NOT on the local wifi network when it is first turned ON, the device broadcast its own wifi access point e.g [SSID: ubuntu-wifi] with [ip: [login to view URL] or [login to view URL]] rather being a station. I then connect my phone to that wifi network [SSID: ubuntu-wifi] via a web browser to [login to view URL] or 192.168.4.1. The webpage provide a list of available WIFI-SSID, then i choose the desired SSID insert the password. At this point, the device switches from Access Point to Station and connect to the internet using the provided password via the desired SSID. [login to view URL]