Customization cgi-sys/defaultwebpage.cgi to an A RECORD with default index

Hello guys, I am making some customizations in my servers and in my whm and i am looking to customize the defaultwebpage.cgi to an different index. This is an example what i want : When a client register a domain through my whmcs and the domain took the default nameservers of my server. After the domain is registered completely, and the customer havent added it yet on any cPanel when we click in his domain ex.www.domain.com automatically displays an index like GoDaddy ( attached ). This happen when the domain is only pointed on default nameservers and not when the customer add it on any cpanel or anything else. I think that should create A Record for index and to point it on this nameservers but i am not clarify. Can anybody help me ? Thank you very much