Send data from website to server?

So I have a website where users create an account and input their steam hex. I have figured out how to send post data to the website then have website return data. I have not figured out how to post from the website to the server. Does anyone have an idea how I could do this? I am specifically trying to post data from a user on the website and update it on the server. What would the code that is receiving it look like?

The SET_HTTP_HANDLER function, perhaps.

i prefer using this resource

So is there like documentation for Set_HTTP_Handler? I’m just confused there is nothing saying how to set it up or anything.

I’ll look into that, thanks.