Your Mac mini provides the following security features to protect what’s on your computer and prevent unauthorized software apps from loading during startup:
Secure storage: Your Mac mini storage drive is encrypted with hardware keys to provide advanced levels of security. In the event of a catastrophic failure, data recovery may not be possible, so you need to back up your files to an external source. See Back up your Mac with Time Machine.
Secure boot and Startup Security Utility: Support for secure boot is turned on automatically. It’s designed to verify that the operating system software loaded on your computer at startup is authorized by Apple. See the Apple Support article Revive or restore Mac firmware in Apple Configurator 2 in the Apple Configurator 2 User Guide.
Learn more. See the Apple Platform Security User Guide.