:
sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/MyUSB download catalina 10157 full installer high quality
: A bootable ISO version is hosted on Internet Archive for archival purposes (approx. 16 GB), though official Apple sources are preferred for security. How to download macOS Catalina : sudo /Applications/Install\ macOS\ Catalina