Yes, if you want to customize how whin works, you need to use mywhin: https://rapidapi.com/inutil-inutil-default/api/mywhin/details

Whin is a service designed to send a WhatsApp to the user subscribed to whin. To prevent spam from the shared gateway, Whin numbers will not send a message to anyone who has not sent a signup message first.
If you operate a business and you need to automate whatsapp operations with your customers through an API interface, you need a private tenant which is what we call mywhin. Visit the link above if you want to give it a try.