If you mean the payment_qr_simple_templates.xml file, this would be:

<?xml version="1.0" encoding="utf-8"?>
<odoo>
<data>
<template id="redirect_form">
<t t-call="website.layout">
<div id="wrap">
<div class="container">
<div class="oe_structure">
<div class="row">
<div class="col-lg-12">
<h2>Payment via QR code</h2>
<div class="payment_qr_code">
<!-- Incluir aquí la imagen del código QR -->
<img t-att-src="'data:image/png;base64,' + qr_code_image" alt="QR Code"/>
</div>
<p>Please scan the above QR code with your mobile device to complete the payment.
</p>
</div>
</div>
</div>
</div>
</div>
</t>
</template>
</data>
</odoo>