VPN basics · Plain-English answer
Your public IP address is the number your internet provider assigns to your connection, and it is what websites see when you visit them. The quickest way to find it is an IP lookup tool, which also shows the rough location and provider associated with the address.
Every website you visit can see your public IP address, so checking it is simple. Open a lookup page such as the free tool at /tools/my-ip/ and it will show the address your connection is currently using, along with the approximate city and the network it belongs to.
If you check while connected to a VPN, you will see the VPN server's address instead of your own. That is a quick way to confirm your VPN is actually working.
Your router has one public IP address facing the internet, while devices on your home network use private addresses like 192.168.1.10 that only exist inside your network. Websites never see those private addresses, only the shared public one.
Most home connections use dynamic addresses, meaning your ISP can change your public IP from time to time. It still identifies your household to every site you visit while it is assigned to you, which is why many people use a VPN to replace it with a shared server address.
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