Where does bottpress get its information?

Completely new to this.

I want to create a botpress chatbot for resl estate agents that handles all the interections with their clients on Facebook and Whatsapp.

people often ask if the property is available or to see pictures. How can the bot know which property the client is refering to? and how can the bot get the inforation, like know if the property is still available or not? Keeping in mind that new property gets added and removed to the list on a daily bases?