Convert the Joomla module code

We need a web programmer. You need to convert the Joomla module code. The 1c exchange module for Joomla 2.5 and PHP 5.3 worked perfectly.
After upgrading to Joomla 3 and PHP 7.2, it had trouble accessing DB because php 7.2 didn’t work compared to 0.
Joomla 3 was removed (require_once (JPATH_BASE .DS.'www'.DS.'libraries' .DS). Joomla. DS. 'user' .DS. 'authentication.php');
We need to fix the code.