Send triggered emails to multiple contacts at same time.

To trigger an email to someone who isn’t the logged in member you will have to write the trigger code in the backend.

The appropriate place to look for guidance on this is in the wix-crm-backend module of the Velo API reference docs - emailContact - Velo API Reference - Wix.com

And more info on how to make a backend module and call it from the front end here: