Hi there @heavyheadco!
Welcome to Klaviyo and the Community! I hope you can utilize our platform as well as this space to learn and develop your business.
If you have not done so already, the first step would be to integrate your Klaviyo store with Shopify. Although Klaviyo maintains a native integration with Shopify, your Klaviyo account is a separate entity from your Shopify account. We have a whole step-by-step process detailing everything about the Shopify integration here.
Once that is completed, you should see that your Shopify contacts also populate within the Klaviyo platform. We also have this help article on how to Sync Shopify Email Subscribers to a Klaviyo List.
More details can be found at:
Something to note is that we can only sync Email, First Name, and Last Name from Klaviyo back to Shopify. Within your Shopify Settings you can click Update Shopify customer profiles with Klaviyo data to sync changes to certain profile fields from Klaviyo to Shopify:
further details can be found at: How to Sync Fields from Klaviyo to Shopify
If you're trying to update the consent status of profiles within Shopify I would recommend reaching out directly to Shopify Support. You may be able to import profiles with consent but Shopify will be able to better guide you on this process.
A community post that details how the data interacts between the two platforms can be also found at:
Hope this helped and thanks for being part of the Community!
Alex