To tell which version of Windows you have, here are a few easy ways:

1. Press the Windows key + R to open the Run dialog, type "winver", and press Enter. This will open a window showing the Windows version, edition, and build number.
2. Go to Start > Settings > System > About. Under "Windows specifications," you can see the edition, version, and OS build of your Windows.
3. Open Command Prompt or PowerShell and type the command: systeminfo | findstr /B /C:"OS Name" /B /C:"OS Version" to get detailed version info.

These methods apply for Windows 10 and Windows 11 systems and show you exactly which version and build you are running.