Stripe Webhook Testing Issue - Test payments don't call the webhook - php

Question

I'm trying to integrate Stripe to accept payments on a website. I've come to the point where pretty much everything works from the client's perspective - test payments go through, everything is integrated and I can do stuff on payment intent succeeded (on the client). However, I can only detect that on the front-end.
Now, I want to show customer some sensitive data when payment is completed. I can't do it on front end - because then client does not even have to pay for that. I need to use webhooks.
So, I've created a sample webhook like this:
require_once 'stripe-php-7.97.0/init.php';
$endpoint_secret = 'endpoint_secret_code';
$payload = #file_get_contents('php://input');
$sig_header = $_SERVER['HTTP_STRIPE_SIGNATURE'];
$event = null;
try {
$event = \Stripe\Webhook::constructEvent(
$payload, $sig_header, $endpoint_secret
);
} catch(\UnexpectedValueException $e) {
// Invalid payload
http_response_code(400);
exit();
} catch(\Stripe\Exception\SignatureVerificationException $e) {
// Invalid signature
http_response_code(400);
exit();
}
ob_flush();
ob_start();
var_dump($event);
file_put_contents("dump.txt", ob_get_flush());
// Handle the event
switch ($event->type) {
case 'payment_intent.succeeded':
$paymentIntent = $event->data->object;
var_dump($event->type);
// ... handle other event types
default:
echo 'Received unknown event type ' . $event->type;
}
http_response_code(200);
I've also created a webhook in the Stripe dashboard, like this:
However, based on the payment amount, I need to do something on this web hook - create a session, store data into the database and so on and so on. I've made it possible with Stripe CLI to test this webhook. However, how to test it using the test payments on the actual page? I have no idea how to do that - it does not work at the moment and without it, I can't be sure that it will work properly once everything goes live until I properly test it like this.
Does anyone have any tips, tutorials, or any kind of help to solve this? I'm pretty much stuck on it so any help would be greatly appreciated.