Preconditions: I installed Magento 2 with sample data used luma theme for customised right now .     Now I'm trying to remove Footer subscriber form  in mycustom theme  which I created before.        As I tried to remove it from layout by m2\vendor\magento\theme-frontend-luma\Magento_Theme\layout\default.xml        Just need to copy paste          <referenceBlock name="form.subscribe" remove="true" />     if you want to remove footer then you remove block like this.           <referenceBlock name="footer_links" remove="true" />     in above file file  m2\vendor\magento\theme-frontend-luma\Magento_Theme\layout\default.xml     default.xml  file used to change layout of page if file doesn't exist then you can create your own file   <?xml version="1.0"?>     <page layout="1column" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"          xsi:noNamespaceSchemaLocation="../../../../...