Current Task (hard-coding custom user registration page using wp_insert_user() )
1- add text captcha & custom user meta fields ('start date', 'end date', 'issue no')
2- trigger/call for an already exist API url (on registration completeness)
3- simple PNG image creation with PHP using text string only (on registration completeness)
NOTE1: Registration Form Design (Html and CSS) has been designed for wp already & will be provided..