magento-test/app/code/Magento/Checkout/Test/Mftf/Section/CheckoutHeaderSection.xml

<?xml version="1.0" encoding="UTF-8"?>
<!--
 /**
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
-->
<sections xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:mftf:Page/etc/SectionObject.xsd">
    <section name="CheckoutHeaderSection">
        <element name="shippingMethodStep" type="text" selector=".opc-progress-bar-item:nth-of-type(1)" timeout="30"/>
        <element name="reviewAndPaymentsStep" type="text" selector=".opc-progress-bar-item:nth-of-type(2)"/>
        <element name="errorMessageContainsText" type="text" selector="//div[contains(@class, 'message message-error error')]//div[contains(text(), '{{text}}')]" parameterized="true"/>
    </section>
</sections>