Thanks for your response!
I understand that you want to navigate the backend web application using only the front door custom domain, which redirects to your backend URL when traffic reaches the web application hosted on GoDaddy.
To achieve this, you can use original host name preservation by whitelisting the front door custom domain on the backend and using the host header as the same as the original custom domain to select the target host. This way, all navigations will occur via Azure Front Door as shown in the below diagram.
Example: Azure Front Door can be configured with the hostname "xyz.azurewebsites.net" and a host header as the Front Door custom domain to select the target host as shown below.
Backend web application configured with same custom domain.
Note: You need to stop all redirections on the backend web application with techworld.com or change it to techops.afd.net, so that any redirections will not go to techworld.com.
For more understanding about original HTTP host name preservation, you can refer this documentation: Host name preservation - Azure Architecture Center | Microsoft Learn
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