Many websites offer "macOS ISO 64-bit ready to download." Proceed with extreme caution:
If you choose this path, verify the SHA-256 hash against known-good values from community forums (e.g., InsanelyMac or MacRumors). Mac Os Download Iso 64 Bit
You cannot directly "download an ISO" from Apple. Instead, download the official installer via the App Store on a real Mac. Many websites offer "macOS ISO 64-bit ready to download
If you don’t own a Mac, acquiring the installer legally is difficult; Apple’s terms require Apple hardware. If you choose this path, verify the SHA-256
Once the installer (e.g., Install macOS.app) is in your /Applications folder, use Terminal to create a 64-bit ISO.
Solution: A full macOS installer ISO should be 8–14 GB. If yours is smaller, it’s likely a recovery-only image or a 32-bit version (for Mac OS X Leopard or earlier). Download again.