29 years on the World Wide Web!
💡 : If you are trying to revive an old Mac, check if it can support High Sierra or Mojave first, as they offer better app compatibility. If you'd like, I can help you with: The exact terminal commands to create a bootable USB. Checking if your specific Mac model can run a newer OS. Finding archived versions if the App Store link fails. How to download and install macOS - Apple Support
shasum /path/to/your/Installer.dmg