Thanks for sharing your question with our network.
Typically when a store installs a post-purchase extension app, they will find additional settings become available in their Shopify Admin. A post-purchase page only displays in your store's checkout if you've completed the configuration in the app settings.
From your Shopify admin, clickSettings.
In thePost-purchase pagesection, select the checkout app that you want to use.
I trust that answers your question, but please let me know if I have missed or misunderstood anything.
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