It was added in macOS 13. You can access it in Preview (Tools menu->Remove Background) or as a Service/Quick Action in Finder (right click an image, Quick Actio

It was added in macOS 13. You can access it in Preview (Tools menu->Remove Background) or as a Service/Quick Action in Finder (right click an image, Quick Actions->Remove Background, or click Customise... to enable it if it's hidden) You can also do it on iOS by long pressing the foreground subject of an image in the photos app.