Looking to automate tedious emails that involve attaching a PDF. Could this be automated without external tools?

hi Reddit

I'm currently working in logistics, and part of our operations workflow is emailing out confirmation letters indicating due dates and type of work received, then shipping/delivery email which contains tracking number we ship out via 3PL, and also an attached invoice.

The former is very easy to setup, I already have exported our database with email lists to send out confirmation letters easily. I also wan't to automate the latter, as due to the sheer volume of emails to send out, this soaks up an hour of time each day.

Cutting down as much time as possible doing tedious tasks like these will help tremendously in scaling our operations. Is there any solution to this with just using Excel?