How to retrieve data from API with headers?

First of all sorry for asking such basic question. I'm new to laravel and API and I stuck with this problems for 3 weeks. I've already search the solution online, but no result. The question is how do I connect an API to my project and get the data? I've already try cURL request, but it give me error say that "Failed to connect to roost.mobsocial.net port 443: Connection refused". This is my code:

   $username='myuss';
       $password='mypass';
       $data=$username.$password;
       $secretkey='uss@pass';
       $authentication=hash_hmac('sha256',$data,$secretkey);

        //get method
        $curl = curl_init();

        curl_setopt_array($curl, array(
            CURLOPT_URL => "https://roost.mobsocial.net/roostClient/",
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_ENCODING => "",
            CURLOPT_TIMEOUT => 30000,
            CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
            CURLOPT_CUSTOMREQUEST => "GET",
            CURLOPT_HTTPHEADER => array(
                // Set Here Your Requesred Headers
                'Content-Type: application/json',
                'Authentication: '.$authentication
            ),
        ));
        $response = curl_exec($curl);
        $err = curl_error($curl);
        curl_close($curl);

        if ($err) {
            echo "cURL Error #:" . $err;
        } else {
            print_r(json_decode($response));
        }