In the PWR Forms application, we provide Setup(tab) in which you can configure Layouts and List Views. The layout helps salesforce users to Create a UI with low to no coding knowledge, using readily available components, you can define a business process or Automation using Workflow in the Layout. List View helps salesforce users to show a record of different objects in one frame, and perform various operations.
For Creating a Layout you need to add the URL Which will redirect to your Layout. Without adding the remote site URL you will not be able to create any Layouts. as shown in the below image
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In the above image, you can see with endpoint URL error just copy the URL and Add the URL to the Remote Site Settings for using the PWR Forms application
Go to the Remote Site Settings
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Click on New Remote Site
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Give a name to the Remote site Setting
In the "Remote Site URL" Paste the copied URL
Click on Save