The next screen describes what Boot Camp assistant does, and warns you to back up your disk if you haven't already done so. I want Windows 7 since some programs I need don't work the best on Windows 10. If you just want to install Windows 7 in a MacBook Pro, others have offered the solution. Option 1: Download Windows 10 on a macOS Catalina With BootCamp. Resize your partition, backup your catalina boot drive, downgrade to Sierra or lower if you can, install windows 7 with bootcamp assistant, then restore your boot drive to catalina.
