Wordpress Simple Plugin Mail File

<?php
/*
plugin name:Registration0
Description:Plugin For Registration.
*/
?>
<?php
define('TEST_PLUGIN_URL',plugin_dir_url(__FILE__));
wp_register_style('test.css', TEST_PLUGIN_URL.'css/test.css');
wp_enqueue_style('test.css');
wp_register_script('jquery.js', TEST_PLUGIN_URL.'js/jquery.js', array('jquery'));
wp_enqueue_style('jquery.js');
?>
<?php
function create_test_table(){
global $wpdb;
$table_name = $wpdb->prefix."registration";
$sql = "CREATE TABLE " .$table_name."
(id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY,
regi_no INT(11) NOT NULL,
 pdf VARCHAR(255) NOT NULL)";
  $wpdb->query($sql);
}
register_activation_hook(__FILE__,'create_test_table');
function test_remove(){
global $wpdb;
$table_name = $wpdb->prefix ."registration";
$sql = "DROP TABLE ". $table_name;
$wpdb->query($sql);
}
register_deactivation_hook(__FILE__,'test_remove');

add_action('admin_menu', 'admin_test_menu');
function admin_test_menu(){
add_menu_page(__('Insert Data','insert_data'),__('Insert Data','insert_data'),'administrator','custompage','custom_page');
add_submenu_page('custompage','Fetch Data','Fetch Data','administrator','sub','custom_subpage');
}
function custom_page(){
include"insert_data.php";
}
function custom_subpage(){
include"fetch_data.php";
}
?>