Install macOS

After starting up from macOS Recovery, follow these steps to install macOS: Choose Reinstall macOS (or Reinstall OS X) from the Utilities window.

Click Continue, then follow the onscreen instructions to choose your disk and begin installation.

How do I reinstall Windows 10 after replacing my hard drive?

How to reinstall Windows 10 to a new hard drive

• Back up all of your files to OneDrive or similar.
• With your old hard drive still installed, go to Settings>Update & Security>Backup.
• Insert a USB with enough storage to hold Windows, and Back Up to the USB drive.
• Shut down your PC, and install the new drive.

What is a clean install when would you perform a clean install of an operating system?

A clean install is an operating system (OS) installation that overwrites all other content on the hard disk. Unlike a typical OS upgrade, a clean install removes the current operating system and user files during the installation process.