Functions examples to remove menu and submenu pages in admin wordpress.

debug_remove_menu_admin.php

if (!function_exists('debug_admin_menus')):
function debug_admin_menus() {
if ( !is_admin())
        return;
    global $submenu, $menu, $pagenow;
    if ( current_user_can('manage_options') ) { // ONLY DO THIS FOR ADMIN
        if( $pagenow == 'index.php' ) {  // PRINTS ON DASHBOARD
            echo '<pre>'; print_r( $menu ); echo '</pre>'; // TOP LEVEL MENUS
            echo '<pre>'; print_r( $submenu ); echo '</pre>'; // SUBMENUS
        }
    }
}
add_action( 'admin_notices', 'debug_admin_menus' );
endif;

remove_menu_admin.php

   // PLUGINS THAT ADD AS DASHBOARD SUBMENU
    // IF THIS IS THE URL BELOW - THE PAGE VARIABLE IS WHAT I NEED ( SO WHATEVER COMES AFTER PAGE= )
    // http://example.com/wp-admin/index.php?page=iconize-plugin-update-notifier
    remove_submenu_page( 'index.php', 'iconize-plugin-update-notifier' );

    // OR FOR EXAMPLE WOOCOMMERCE DASHBOARD SUBMENU
    remove_submenu_page( 'index.php', 'wc-about' ); //WOO
    remove_submenu_page( 'index.php', 'wc-credits' ); //WOO
    remove_submenu_page( 'index.php', 'wc-translators' ); //WOO

    // CUSTOM POST TYPE TOP LEVELS
    remove_menu_page( 'edit.php?post_type={$POST_TYPE}' ); //LOOK FOR WHAT COMES AFTER POST TYPE IN THE URL
    remove_menu_page( 'edit.php?post_type=testimonials-widget' ); //TESTIMONIALS WIDGET
    remove_menu_page( 'edit.php?post_type=product' ); //WOOCOMMERCE

    // CUSTOM POST TYPE SUBMENU
     remove_submenu_page( 'edit.php?post_type={$POST_TYPE}', '{$SUBMENU_URL_VARIABLE}' ); //EXAMPLE FORMAT
     // SO IF BELOW IS THE URL
     // http://example.com/wp-admin/edit.php?post_type=testimonials-widget&page=testimonialswidget_settings
     // YOU NEED TO SEE WHATS AFTER PAGE
     remove_submenu_page( 'edit.php?post_type=testimonials-widget', 'testimonialswidget_settings' ); //TESTIMONIALS WIDGET

    // OTHER EXAMPLES
    remove_menu_page( 'revslider' ); // REVSLIDER
    remove_menu_page( 'woocommerce' ); // WOOCOMMERCE
    remove_menu_page( 'order-post-types-shop_order' ); // WOOCOMMERCE
    remove_menu_page( 'order-post-types-shop_coupons' ); // WOOCOMMERCE
    remove_menu_page( 'shortcodes-ultimate' ); // SHORTCODES ULTIMATE
    remove_menu_page( 'wp-admin-microblog/wp-admin-microblog.php' ); // ADMIN MICROBLOG
    remove_menu_page( 'snippets' ); //CODE SNIPPETS
    remove_menu_page( 'gf_edit_forms' ); // GRAVITY FORMS
        remove_submenu_page( 'gf_edit_forms', 'gf_settings' ); // GRAVITY FORMS
        remove_submenu_page( 'gf_edit_forms', 'gf_export' ); // GRAVITY FORMS
        remove_submenu_page( 'gf_edit_forms', 'gf_update' ); // GRAVITY FORMS
        remove_submenu_page( 'gf_edit_forms', 'gf_addons' ); // GRAVITY FORMS
        remove_submenu_page( 'gf_edit_forms', 'gf_help' ); // GRAVITY FORMS

        remove_submenu_page( 'cleverness-to-do-list', 'cleverness-to-do-list-settings' ); //Cleverness TODO