Question:
I would like to ask about uploading a file using HTML. I have the code, but the problem is that I can not receive and save the file that I sent from the HTML code. (The upload uses the form “POST” method with multipart/form-data.)

Answer:
File upload from the HTML side is extremely simple as you have pointed out.

On the server side, to receive and save the file, you will need custom code. You could write this yourself, or purchase third-party products that do this for you.