Hi Lara!
Thanks for getting in touch with us!
You will need to setup your Event Aggregator license. Please follow the steps in https://theeventscalendar.com/knowledgebase/finding-and-inputting-your-license-key/ to activate your Event Aggregator license in your site.
Once you are done with that, you will be able to import events from Eventbrite with the event URL. Simply navigate to your WP Admin > Events > Imports and select Eventbrite as the import source.
The first time you import from Eventbrite, you’ll be prompted to log in to Eventbrite and then allow Event Aggregator to connect with your Eventbrite account. This will allow Event Aggregator to “talk” to that source and gather events data.
You can also review your connection by going to Events → Settings → APIs.
Let me share the following article that will get you started with Event Aggregator > https://theeventscalendar.com/knowledgebase/new-user-primer-event-aggregator/
I hope that helps. Let me know if any follow up question.
Best,
Victor