Send email from gmail alias with ssmtp or other

I’m trying to set up alerts for some services on some of my linux servers. So I looked into ssmtp package.

I can use it to send emails from a gmail account I made for my services. And since I own a google domain, I decided to do an email alias, [email protected] with it redirecting to the gmail account I just made.

I then, in gmail, set it up so I can send emails from that address by adding it as an inbox alias, logging in with the gmail account I made (the same account it’s being sent to), and verifying the address.

So now, in gmail, I can send and receive emails from that address.

But how can I make it so I can send from that address in other programs other than gmail, such as ssmtp?