Some Macs on High Sierra can directly install macOS Big Sur (11) or Monterey (12) without installing Catalina first, provided they meet hardware requirements.
Because you are running High Sierra, you may not see Catalina in "Software Update" within System Preferences. You must use the App Store: macOS - How to Upgrade - Apple (SI) how to update macos high sierra 10136 to 1015
Before upgrading to Catalina, you must ensure your High Sierra installation is fully updated. The version number “10.13.6” is the final build of High Sierra. To verify, go to . If you see a lower version (e.g., 10.13.5), open System Preferences > Software Update and install all available security updates for High Sierra until you reach 10.13.6. This ensures compatibility with the Catalina upgrade mechanism. Some Macs on High Sierra can directly install
You can skip Mojave entirely – the Catalina installer works directly from High Sierra. The version number “10
Elias took a deep breath. He knew he had to be careful. He plugged in his external hard drive and ran a Time Machine backup. "Better safe than sorry," he whispered, watching the progress bar fill up.