See the public IP address the internet sees when you connect - IPv4 and IPv6, your internet provider and an approximate location. You can also look up any other IP address.
An IP address is the number that identifies your connection on the internet, the way a postal address identifies a house. Websites use it to know where to send the page you asked for.
The location is guessed from the IP address, so it usually shows the city of your internet provider's network, not your exact home. On mobile data or a VPN it can be in a different city or even another country.
IPv4 addresses look like 203.0.113.7 and are running out. IPv6 addresses are longer (2001:db8::1) and there are plenty of them. Many connections now have both.
Sharing it is normal - every site you visit sees it. It does not reveal your name or exact address, but you should still avoid posting it publicly, and a VPN hides it if you need more privacy.