Hi Fatma,
This functionality does not exist in the product at this point in time. You can always download the badges/certificates in bulk on the backend or include a data tag in Cvent emails to send them to individual attendees for them to download their own, but there isn't a report that houses the links to all of them. I would recommend submitting this as an enhancement request within Participate > Product Ideas for our product team to consider for future releases.
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Julia Plymack
Senior Customer Success Manager
Cvent
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