command line - understanding sending post request (with curl)

alright, I know related questions have been answered :

What is the cURL command-line syntax to do a POST request?

https://stackoverflow.com/questions/14978411/http-post-and-get-using-curl-in-linux

but my question is rather more basic,

Supposedly we have the following form in a html page:

echo your name:

Once botton is clicked , it basically echos what ever is typed in the text box

So my question is how exactly do the same thing with "curl".
what do I need to echo my name?

server is running locally. I can't provide the link. but let's say its running at http://www.example.com

EDIT 1 :

this is how progress Function look like :