Can you download a list of registrants for an event?

If you've added an event in a calendar app is there any ability to download a list of community members that have registered? Or a way to communicate with those registrants other than the automated notifications they get? i.e. send a message to all registrants of a specific event to include an online zoom link or suchlike? 

I can't see any way of manually invoking a message to go to all registrants so thought maybe if you could download a list of registrants instead and use an external email service to send something out instead. But I can't see a way of downloading that information either? 

Any suggestions?