$curl = curl_init();
$data = array(
"amount" => "15",
"currency" => "USD",
"order_id" => "1",
"url_return" => "https://your.site/return",
"url_callback" => "https://your.site/callback"
);
$headers = array(
"merchant: 8b03432e-385b-4670-8d06-064591096795",
"sign: fe99035f86fa436181717b302b95bacff1",
"Content-Type: application/json"
);
$options = array(
CURLOPT_URL => "https://api.cryptomus.com/v1/payment",
CURLOPT_POST => true,
CURLOPT_RETURNTRANSFER => true,
CURLOPT_POSTFIELDS => json_encode($data),
CURLOPT_HTTPHEADER => $headers
);
curl_setopt_array($curl, $options);
$response = curl_exec($curl);
curl_close($curl);