magento-test/app/code/Magento/Checkout/Test/Mftf/ActionGroup/PlaceOrderWithLoggedUserActionGroup.xml

<?xml version="1.0" encoding="UTF-8"?>
<!--
 /**
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
-->

<actionGroups xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
              xsi:noNamespaceSchemaLocation="urn:magento:mftf:Test/etc/actionGroupSchema.xsd">
    <actionGroup name="PlaceOrderWithLoggedUserActionGroup">
        <annotations>
            <description>Clicks on 'Proceed to Checkout' on the Storefront Shopping Cart page. Selects the provided Shipping Method. Clicks on Next. Clicks on Place Order. Validates that the Success Message is present and correct.</description>
        </annotations>
        <arguments>
            <!--First available shipping method will be selected if value is not passed for shippingMethod-->
            <argument name="shippingMethod" defaultValue="" type="string"/>
        </arguments>

        <waitForLoadingMaskToDisappear stepKey="waitForCartTotalsLoaded"/>
        <waitForElementVisible selector="{{CheckoutCartSummarySection.orderTotal}}" stepKey="waitForCartGrandTotalVisible"/>
        <waitForElementVisible selector="{{CheckoutCartSummarySection.proceedToCheckout}}" stepKey="waitProceedToCheckout"/>
        <click selector="{{CheckoutCartSummarySection.proceedToCheckout}}" stepKey="clickProceedToCheckout"/>
        <click selector="{{CheckoutShippingMethodsSection.checkShippingMethodByName('shippingMethod')}}" stepKey="selectShippingMethod"/>
        <waitForElement selector="{{CheckoutShippingSection.next}}" stepKey="waitForNextButton"/>
        <click selector="{{CheckoutShippingSection.next}}" stepKey="clickNext"/>
        <waitForElement selector="{{CheckoutPaymentSection.paymentSectionTitle}}" stepKey="waitForPaymentSectionLoaded"/>
        <seeInCurrentUrl url="{{CheckoutPage.url}}/#payment" stepKey="assertCheckoutPaymentUrl"/>
        <waitForElementVisible selector="{{CheckoutPaymentSection.placeOrder}}" stepKey="waitForPlaceOrderButton"/>
        <click selector="{{CheckoutPaymentSection.placeOrder}}" stepKey="clickPlaceOrder"/>
        <see selector="{{CheckoutSuccessMainSection.successTitle}}" userInput="Thank you for your purchase!" stepKey="waitForLoadSuccessPage"/>
    </actionGroup>
</actionGroups>