Hi Cate,
You can create custom event fields for this which would appear in the creation process of an event. The article below outlines how to create custom event fields and how to fill them out when creating an event.
https://support.cvent.com/s/communityarticle/Using-Custom-Event-Fields?is_article=true&lang=en_US&searchFor=custom%20event%20fields&page=1
Once these are created, you can run a cross-event report and bring in the event custom field, to see what attendees reigstered for each event.
Thank you!
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Erica Kennedy
Senior Client Success Manager
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