Create a Spring Boot project with the necessary dependencies.
Implement a controller class to handle HTTP requests.
Use the @RequestMapping annotation to map a method to a specific HTTP endpoint.
Add the produces attribute to the @RequestMapping annotation to specify the response content type as JSON.
Use the @RequestHeader annotation to extract values from HTTP headers.
Set the value attribute of @RequestHeader to the header name, and use the defaultValue attribute to provide a default value if the header is not present.
Use the MediaType.APPLICATION_JSON_VALUE constant from the org.springframework.http.MediaType class to set the "Content-Type" header to "application/json" in the response.
Return the response object with the appropriate data.
Ensure that the application.properties or application.yml file includes the necessary server port configuration.
Run the Spring Boot application and test the endpoint using a tool like cURL or Postman.