Hi @maiamum
Great question! The "how did you hear about us?" drop-down isn't a native feature of Shopify themes, so did you implement that in your old theme by way of an app?
The best workaround to achieve a similar result is to insert the order notes feature into your cart. This is usually used to collect instructions from customers, but you can edit the language of it to instead ask them to describe how they heard about you. Here is how you get more information with order notes.
Of course, it would also be great to identify whether you did in fact use an app that helped you achieve this effect in the Debut theme. If you go to Online Store > Apps can you see an app there that might be utilized to add a feature like that? You could reach out to the app developers to ask about finding and retrieving the code for that app and inserting it into your Dawn theme.
Alternatively, did you hire a third party to custom code this feature in?
If you're looking to delve more into customer acquisition to understand the journey that customers took to find your brand, I'd recommend checking out Shopify Analytics. Specifically have a look at these reports that show you where your customers are coming from, what device they're using, what social media they found you on, and so on:
There's more information on that in our help guide on Shopify Analytics.
I look forward to hearing more from you!
