Hello, the event emails are designed to be sent automatically when you add somebody to the Invited list. You can change this behavior yourself by modifying the pipeline which drives the event. 

Click on "Event Attendees" to open the pipeline, and then click on "Edit Stages" and "Edit Templates" to modify the email automation or the emails themselves.

We would like to send all people registered on this dashboard for inviting this evnet. I add my self as one of the prospect on dashbord as test. But we do not receive any invitation email when the event launched automatically.  We also do not know who are on invited list and do not know how to add the people to invitation list. We just get lost as follow.