To create a new menu item in the WordPress admin dashboard, use the add_menu_page() function. This allows you to display custom content or features. Step 1: Go to your active theme’s functions.php or create a new plugin file. Step 2: Paste this code:

function register_custom_admin_menu() {
    add_menu_page(
        'Custom Menu',         // Page title
        'Custom Menu',         // Menu label
        'manage_options',      // Capability
        'custom-menu',         // Menu slug
        'render_custom_menu',  // Callback function
        'dashicons-admin-generic', // Icon
        25                     // Position
    );
}
add_action('admin_menu', 'register_custom_admin_menu');

// Callback function to render menu content
function render_custom_menu() {
    echo '<div class="wrap"> '; 
        echo '<h1>Custom Menu</h1> '; 
        echo 'This is your custom admin menu page content.'; 
    echo '</div> '; 
}

  Step 3: Save changes. You’ll now see a “Custom Menu” link in the WordPress admin menu. This is ideal for plugin interfaces, reports, or internal admin-only tools. You can expand this further with submenus using add_submenu_page().