macOS High Sierra - Technical Specifications - Apple Support
Are you installing this on an or a third-party replacement drive? Which error message (if any) are you currently seeing? download+macos+high+sierra+10136+dmg+mac+install
Type the following command: softwareupdate --fetch-full-installer --full-installer-version 10.13.6 macOS High Sierra - Technical Specifications - Apple
Select or System Preferences > Software Update . If you are encountering errors with Terminal commands
If you are encountering errors with Terminal commands or need to bypass hardware restrictions for an unsupported Mac, several popular patcher tools are available.
If you are currently on a much newer version of macOS (like Ventura or Sonoma), the High Sierra installer may refuse to run. In that case, creating a bootable USB is the only way to downgrade. How to download and install macOS - Apple Support
To help refine these instructions for your specific setup, please share a few details: What is the of the Mac you are targeting? Are you downloading this file from a Mac or a Windows PC ?