Apple provides a direct download link for the file, which contains the Install macOS Sierra.app installer. Download macOS Sierra from Apple Support 2. Verify the Installer

Visit the official page for downloading older macOS versions. Locate the macOS Sierra 10.12 link.

Rename Sierra.iso.cdr to Sierra.iso .

If you are looking to revive an older Mac, test legacy software, or set up a virtual machine, downloading the macOS 10.12 Sierra full installer is the essential first step. Released in 2016, macOS Sierra introduced Siri to the Mac, optimized storage solutions, and brought Apple Pay to the web.

Double-click and run through the standard onscreen extraction menus.

curl -O https://swcdn.apple.com/content/downloads/00/42/061-28683/owvxi67czq832leirn2heal5ovhbhymd7y/InstallMacOS.pkg