To restart your Mac in Safe Mode, the process depends on whether your Mac has Apple silicon or an Intel processor:

• For Apple silicon Macs:
  1. Choose Apple menu > Shut Down and wait for the Mac to completely power off.
  2. Press and hold the power button until “Loading startup options” appears.
  3. Select your startup disk.
  4. Press and hold the Shift key, then click "Continue in Safe Mode."
  5. Your Mac restarts and when the login window appears, "Safe Boot" should show in the menu bar.
• For Intel-based Macs:
  1. Turn on or restart your Mac.
  2. Immediately press and hold the Shift key.
  3. Release the key when the login window appears.
  4. Log in (you may need to log in twice if FileVault is enabled).
  5. You should see “Safe Boot” in the menu bar at the login screen.

To verify if your Mac started in Safe Mode, you can check the System Information app under Software > Boot Mode, which should say "Safe." The login window also displays “Safe Boot” in the screen's corner when in Safe Mode.