Apple does not provide official macOS Monterey ISO files for direct download. Instead, you must download the full application from Apple's servers and use the Mac Terminal to create the ISO yourself . 1. Download the Full Installer
With the installer in your Applications folder, open Terminal to create the ISO through these steps: How to download and install macOS - Apple Support Download File MacOS Monterey 12.4 (21F79).iso
: Open Terminal and run the command: softwareupdate --fetch-full-installer --full-installer-version 12.4 . Apple does not provide official macOS Monterey ISO