Top link in magento can be added/removed by creating custom xml files. In this xml file you will add code to remove these top links. You can add/remove top link in magento using following method.

Create custom default.xml file  at following path

app/code/[Name_Space]/[Your_Module]/view/frontend/layout

Luma Theme:

If the theme you are using is Luma or extends Luma theme than put the following code in default.xml to remove top link

<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
<body>
   <!-- you can easly add New links with following code -->
   <referenceBlock name="header.links">
      <!-- Custom Link -->
      <block class="Magento\Framework\View\Element\Html\Link" name="contactus.link" after="register-link">
         <arguments>
            <argument name="label" xsi:type="string" translate="false">Custom Link</argument>
            <argument name="path" xsi:type="string" translate="false">link-1</argument>
         </arguments>
      </block>
 
      <!-- you can easly Remove links with following code -->
      <referenceBlock name="register-link" remove="true" /> <!--for Create Account Link-->
      <referenceBlock name="authorization-link" remove="true" /> <!--for Sign In Link -->
      <referenceBlock name="wish-list-link" remove="true" /> <!--for WishList Link-->
      <referenceBlock name="my-account-link" remove="true" /> <!--for My Account Link-->
 
   </referenceBlock>
</body>
</page>

Blank Theme:

If the theme you are using is Blank Theme or extends Blank Theme than put the following code in default.xml

<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
<body>
   <!-- you can easly add New links with following code -->
   <referenceBlock name="top.links">
      <!-- Custom Link -->
      <block class="Magento\Framework\View\Element\Html\Link" name="contactus.link" after="register-link">
         <arguments>
            <argument name="label" xsi:type="string" translate="false">Custom Link</argument>
            <argument name="path" xsi:type="string" translate="false">custom-link</argument>
         </arguments>
      </block>
      <!-- you can easly Remove links with following code -->
      <referenceBlock name="register-link" remove="true" /> <!--for Create Account Link-->
      <referenceBlock name="authorization-link" remove="true" /> <!--for Sign In Link -->
      <referenceBlock name="wish-list-link" remove="true" /> <!--for WishList Link-->
      <referenceBlock name="my-account-link" remove="true" /> <!--for My Account Link-->
 
   </referenceBlock>
</body>
</page>

You can also create default.xml in the following location.

<Theme_Dir>/Magento_Theme/layout/default.xml

and put the above code to add/remove links.