You'll open Shopify's checkout editor and drop the Zenith survey block onto the two pages customers see after they buy: the Thank you page and the Order status page. Placing it on both means every customer sees it, whether they land on the confirmation right after checkout or return later to check their order.
In your Shopify admin, click Settings in the bottom-left corner.

Choose Checkout from the left menu, then click the black Edit button next to your active configuration.

Open the page selector at the top of the editor. You'll place the survey on two pages here: Thank you (under Post purchase) and Order status (under Customer accounts). Start by choosing Thank you.

In the Main or Order summary section, click ⊕ Add block, then select Post Purchase Survey under Zenith: Post Purchase Survey.

Click Save in the top-right. The block is now placed on your Thank you page.

Open the page selector again and choose Order status under Customer accounts. Just like before, click ⊕ Add block, select Post Purchase Survey, and Save. The block is now placed on both pages.
