Revision c9b05c6c-5696-4491-a0dd-f6e967386fa9

Add below files into your custom module 

Ex:-Namespace:- Mytest Modulename : Myemail;  
1 Create customer_account.xml into Mytest/Myemail/view/frontend/layout

    <page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
        <body>
            <referenceBlock name="customer_account_navigation">
                <block class="Magento\Framework\View\Element\Html\Link\Current" name="customer-account-navigation-myemail">
                    <arguments>
                        <argument name="path" xsi:type="string">myemail/customer/index</argument>
                        <argument name="label" xsi:type="string"> MyEmail</argument>
                    </arguments>
                </block>
            </referenceBlock>
        </body>
    </page>

2.Create myemail_customer_index.xml into Mytest/Myemail/view/frontend/layout

    <page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../../../lib/internal/Magento/Framework/View/Layout/etc/page_configuration.xsd">
    <update handle="customer_account"/>
    <body>
        <referenceBlock name="page.main.title">
                <action method="setPageTitle">
                    <argument translate="true" name="title" xsi:type="string">MyEmail</argument>
                </action>
         </referenceBlock>
         <referenceContainer name="content">
            <block class="Magento\Framework\View\Element\Template" name="my_email" template="Mytest_Myemail::test.phtml">
            </block>
        </referenceContainer>
    </body>
    </page>

3 Create Index.php into Mytest/Myemail/Controller/Customer

    <?php
    namespace Magik\Ageverifier\Controller\Customer;
    
    class Index extends \Magento\Framework\App\Action\Action {
    
     public function execute() {
    
        $this->_view->loadLayout();
    
        $this->_view->renderLayout();
      }
    
    }

4.Create test.phtml into Mytest/Myemail/view/frontend/templates

    <?php // Add some code ?>