Open Postman. Create a new request. Name your request, e.g., "Process Diagnostic Report". Choose "POST" as the HTTP method. Enter the request URL: http://localhost:3000/processDiagnosticReport. Click on the "Body" tab. Select "form-data" as the body type. Click on the "Choose Files" button and select the PDF file. Click on the "Send" button to send the request. View the response in the "Response" section. key of pdf file for uploading is "file"