In two step you're done !
You need to install unattended-upgrades from APT repository.
apt install unattended-upgrades
Now you need to configure properly the package.
Enable Email Notification
# uncomment in /etc/apt/apt.conf.d/50unattended-upgrades Unattended-Upgrade::Mail "Myemail@example.com";
Check this file /etc/apt/apt.conf.d/50unattended-upgrades many options are available.
TAG: DEBIAN , SECU