Using cURL To Make a REST Request - UND-Robotic-Mining-Team/Master-Guide GitHub Wiki
To use cURL in your program, you first need to include it:
#include <curl.h>
If it fails on this include, you may need to run sudo apt install libcurl
or similar to install.
https://biarri.com/using-libcurl-to-make-web-requests-from-a-c-program/