Software that is able to communicate with us this software using the messenger platform to talk with the
customers and potential customers.

To build a ChatBot it is necessary to have a Facebook Page where chatbot gotta be implemented.
An example to this technology is the chatbot from https://www.facebook.com/NUMAmexico/
If you wanna see how this works send a message to NUMAmexico (https://www.facebook.com/NUMAmexico/ ) in Messenger.