If you do not have access to a Mac, use these pre-converted images. These files are bootable and ready for VMware, VirtualBox, or USB flashing.
If you have the "Install macOS Catalina.app" in your Applications folder, you can use the Terminal to convert it into a clean ISO for virtualization. and run these commands one by one: download macos catalina 10.15 iso and dmg image
To download macOS Catalina 10.15 ISO and DMG images, follow these steps: If you do not have access to a