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.
