Hi Jess -
Whether you are starting with a new Email or using an existing email and adjusting it, open up the Email Designer. From the Build menu on the right side, include the Registration Information widget into the body of your email:

This will pull in information from your Registration Form. By clicking in the Registration Information box, it will allow you to customize what parts of the registration information you will want to include. Make sure that the "Display Questions" is toggled on because this will include the responses (which would bring in the Addresses that you are looking to include):

Here's an article that should also walk you through the process:
https://support.cvent.com/s/communityarticle/Using-the-Current-Registration-Data-Tag-or-Registration-Information-Widget?is_article=true&lang=en_US&searchFor=registration%20information%20in%20email&page=1
Hope this helps!
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Rebecca Yousif
Senior Administrator - Event Technology
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