rest service Exception handling in VBCS

Summary: I want to handle the user define exception populate a message in vbcs via data invoking through rest service.

Content (required): I am using post rest service sometimes when the user passes wrong input or any then it gives some error reason in the response message I want to substring or cut the error message content and want to show an error message popup when the post-service failed to invoke data.

Version (include the version you are using, if applicable):Version: 21.10.0

Code Snippet (add any code snippets that support your topic, if applicable):