The way to create and add .set up file for druapl8 customized type knowledge storage…my file is custom_form.set up however my customized module not load this file

<?php /** * Implemetation of hook_schema() */ perform custom_form_schema() { $schema=array();   $schema['custom_form'] = array(        'description' => 'An instance type desk',     'fields' => array(       'fe_id' => array(         'description' => 'Drupal Development Service main identifier for a type.',         'sort' => 'serial',         'unsigned' => TRUE,         'not null' => TRUE,       ),        'firstName' => array(         'description' => 'A area storing textual content',         'sort' => 'textual content',         'size' => 50,         'not null' => TRUE,        ), 'lastName' => array(         'description' => 'A area storing textual content',         'sort' => 'textual content',         'size' => 50,         'not null' => TRUE,               ),  'emailId' => array(          'sort' => 'varchar',         'size' => 50,         'not null' => TRUE,               ),  'move' => array(                 'sort' => 'varchar',         'size' => 50,         'not null' => TRUE,        ),  'likes' => array(        'description' => 'A area storing Likes',         'sort' => 'textual content',         'size' => 200,         'not null' => TRUE,        ),  'gender' => array(         'description' => 'A area storing Gender',         'sort' => 'textual content',         'size' => 50,         'not null' => TRUE,        ),  'description' => array(         'description' => 'A area storing Description',         'sort' => 'textual content',         'size' => 255,         'not null' => TRUE,        ),  ),       'main key' => array('fe_id'),   );   return $schema; } ?>