If your Mac starts up to Options with a gear icon
The startup options window shows icons for each available startup disk, a gear icon labeled Options, and buttons for Shut Down and Restart.
If you're using a Mac with Apple silicon, the startup options window appears when you turn on your Mac and then continue to press and hold the power button.
Here's what you can do in startup options:
Select a startup disk, such as Macintosh HD, which is the disk your Mac starts up from by default. Then click Continue to start up from that disk.
Click Shut Down or Restart.
These hidden features are also available in startup options:
Select a startup disk, such as Macintosh HD, then press and hold the Shift key while clicking “Continue in Safe Mode.” Learn about safe mode.
Press and hold Command (⌘)-D to open Apple Diagnostics.