Deploying App extension to Different FA servers

Summary: Service connections pointing to test servers and API calls failing in dev instance while deploying App extension

Content (required): Hello, I am trying to publish an app extension on different FA servers and I see when it is deployed on a dev instance, the rest API calls in the network tab are going to the test server & not the dev tab. I saw this post ( https://blogs.oracle.com/shay/post/leveraging-application-profiles-to-switch-backend-servers-with-visual-builder-studio) however the options to create a server are not shown or are disabled. I am not sure if I need to create a custom back end. If anyone can point me to the exact steps needed as the option for Application profiles don't seem to be enabled as well