If you’re using an older version of OS X (macOS High Sierra version 10.13 and earlier) you can still install Windows 7. Boot Camp no longer supports Windows 7 and only works with a 64-bit version of Windows 10 Home edition or Windows 10 Professional edition.
It’s a free upgrade from Windows 10 OS if your device meets the minimum requirements. The latest Windows 11 public release has been available for a while now and the latest build is 22000.318 (21H2).