You can find instructions on how to install and use @kahn-hubitat's sendmail driver over here:
You can find instructions on how to install and use @erktrek's email notification driver (Hubitat-DoNS) here:
Note that @erktrek's driver supports encryption, but requires something like an RPi to run on your local network to run a nodeJs server.
While I use @erktrek's implementation, they are both easy to setup and will create devices that work as Notification devices that can be used for notifications within your automations.
