When installation is complete, your Mac might start up to a setup assistant.Your Mac might restart and show a progress bar several times, and the screen might be empty for minutes at a time. Allow installation to complete without putting your Mac to sleep or closing its lid.If the installer doesn't see your disk, or it says that it can't install on your computer or volume, you might need to erase your disk first.If the installer offers the choice between installing on Macintosh HD or Macintosh HD - Data, choose Macintosh HD.If the installer asks to unlock your disk, enter the password that you use to log in to your Mac.Click Continue, then follow the onscreen instructions.When you see a window with the option to reinstall macOS, your Mac has started up from Recovery.

Then click Next and enter that user's administrator password, which is the password they use to log in to the Mac. If you're asked to select a user you know the password for, select the user.To select a Wi-Fi network, use the Wi-Fi menu in the upper-right corner of the screen. You might be asked to select a Wi-Fi network or attach a network cable.Keep holding the keys until you see an Apple logo or spinning globe.Shift-Option-Command-R: When you press and hold these four keys at startup, macOS Recovery might offer the macOS that came with your Mac, or the closest version still available.Option-Command-R: When you press and hold these three keys at startup, macOS Recovery might offer the latest macOS that is compatible with your Mac.Command-R: When you press and hold these two keys at startup, macOS Recovery will offer the current version of the most recently installed macOS.If none of them work, review the guidelines for using startup-key combinations. Immediately after releasing the power button, press and hold one of these key combinations.

Press and release the power button to turn on your Mac.

If you're not using a Mac with Apple silicon, you're using an Intel-based Mac.

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