More than 5 million micro:bits have been shipped and used in many educational scenes around the world. And it can be one of the tools that can physically solve our daily problems (SDGs, etc).
Micro:bit has radio function but it dose not work over 20 meters. You need to buy Wi-Fi module if you want to communicate with micro:bit in the distance.
TFabConnect is the service that micro:bit can connect to the internet via PC browser. So you can easily learn IoT without additional Wi-Fi module and hardware.