payment gateway Integration - Shopping Cart - Core PHP

Phper Required to assist via Anydesk or Visual Code Studio with remote collab mode allow transmit information via a token using ajax.
Estimated time to develop 1-5 hours.

An Example of the token handling function
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define("BASE_URL", "https://api.pay.../V1");
define("MERCHANT_ID", "T16121");
define("PRIVATE_KEY", "T16121_");
define("PUBLIC_KEY", "T16121_PUB_");

createTokenPayment();

function createTokenPayment() {
$headers[] = "Authorization: Basic " . base64_encode(PRIVATE_KEY . ":");
$headers[] = "Content-Type: application/x-www-form-urlencoded";

$post = array(
"customerNumber" => 7,
"merchantId" => MERCHANT_ID,
"transactionType" => "payment",
"principalAmount" => "23.45",
"currency" => "aud",
"orderNumber" => "Sale-Identification"
);

$result = CurlExecutor::execute(BASE_URL . "/transactions", "POST", $post, null, $headers);
$result["response"] = json_decode($result["response"]);
CurlExecutor::prettyPrint($result);
}