An example of Stripe Checkout

create-checkout-session.php

<?php

require __DIR__ . '/../vendor/autoload.php';
// This is a public sample test API key.
// Don’t submit any personally identifiable information in requests made with this key.
// Sign in to see your own test API key embedded in code samples.
\Stripe\Stripe::setApiKey('sk_test_key_here');

header('Content-Type: application/json');

$YOUR_DOMAIN = 'http://localhost:4242';

$checkout_session = \Stripe\Checkout\Session::create([
    'customer_email' => 'customer@example.com',
    'submit_type' => 'pay',
    'billing_address_collection' => 'required',
    'line_items' => [
        [
            "price_data" =>
                [
                    'currency' => 'USD',
                    'product_data' => [
                        'name' => "Product Name",
                        'description' => "Product description..."
                    ],
                    'unit_amount_decimal' => 15000,
                    'tax_behavior' => "inclusive"
                ],
            "quantity" => 2
        ],
        [
            "price_data" =>
                [
                    'currency' => 'USD',
                    'product_data' => [
                        'name' => "Card Fee",
                        'description' => "3% of total"
                    ],
                    'unit_amount_decimal' => 900,
                    'tax_behavior' => "exclusive"
                ],
            "quantity" => 1
        ],
    ],
    'mode' => 'payment',
    'success_url' => $YOUR_DOMAIN . '/success.html',
    'cancel_url' => $YOUR_DOMAIN . '/cancel.html',
    'automatic_tax' => [
        'enabled' => false,
    ],
]);

// the payment intent contains an ID which can be used to redirect a customer service agent to the transaction
//var_dump($checkout_session->payment_intent);
//die();

header("HTTP/1.1 303 See Other");
header("Location: " . $checkout_session->url);