Need a c++ private function for web api with winhttp.h

Hello,

I need a c++ private function for web api with winhttp.h. I´m using dev c++ 5.11.
The public funtion is done and working but I have no idea about how to set the headers.

There is an example of public and private link and the public function on the source file. The public one is returning the server time
You should register to generate your own api keys for private calls. The two screenshoots show you how to generate a private key. Only "query funds" needed for this example, but enable what you need.

Here is the api documentation link. Feel free to read what you need, but with capter 1"General Usage" should be enough.
https://www.kraken.com/help/api

Thank you so much.