I understand that, file will not get uploaded unless the developers have written the code to revcieve those files. Please correct me if I have understood it incorrectly. I cannot directly upload a file where web servers have enabled http PUT request.
Not quite. Some servers may have built-in capabilities to handle uploads (in which case
you should check the server's documentation for how that works, and where files will end up).
But you were talking about a .Net application, so I assumed that's what handles the upload.