How to use json to pass data from a php file to another php file

Question

As mentioned earlier , i am working on the local server as of now in xampp. I have created 2 files index.php and test.php. What i want to achieve is that , index.php will send json data to test.php , with the json data received , the test.php is able to use that json data to turn the statistics into graph.

I am working with the first step , but however , nothing seems to display on my test.php when i tried to do a var_dump($data) , and what i get is NULL. Tried alot of solutions online but none to seems to fix it. I am relatively new to this , so really thanks and appreciate of your help. First php is index.php , second php is test.php.

Do i require a live server as of now in order to see the results in test.php or local server unable to display the result?

    <?php 
$array = array();
$product = array();
$product[0]['id_product'] = 'A01';
$product[0]['name_product'] = 'Sandal';
$product[0]['price_product'] = '500';
 
$product[1]['id_product'] = 'A02';
$product[1]['name_product'] = 'Shoes';
$product[1]['price_product'] = '2500';
 
$array['id'] = '123';
$array['note'] = 'this is my short example';
$array['data'] = $product;
 
$data = json_encode($array);
$ch = curl_init('http://localhost:8080/practice3/test.php');  
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");                     
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);                   
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);  
curl_setopt($ch, CURLOPT_POST, count($data));                                          
$result = curl_exec($ch);
var_dump($result);
?>
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<?php
$fp = fopen('php://input', 'r');
$raw = stream_get_contents($fp);
$data = json_decode($raw,true);

echo "hello";

echo $data['id'];
echo $data['note'];
foreach ($data['data'] as $key) {
 echo 'id_product : '.$key['id_product'].'<br/>';
 echo 'name_product : '.$key['name_product'].'<br/>';
 echo 'price_product : '.$key['price_product'].'<br/>';
}
?>
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