No, WiFi cannot work without an internet connection. The internet is what users subscribe to through their ISP. Without this, a wireless connection cannot be established. Internet connection and WiFi are two different things. To get an internet connection, users will have to subscribe monthly to an internet plan that will be priced based on internet speeds.
Ethernet cables and WiFi routers are some of the ways by which devices can connect to the internet. Routers enable devices to connect to the internet without the need for a physical connection but cannot work without an internet connection.