AI Chatbot Addon

We have developed a digital visitor management platform enabling visitors to scan a QR code with our visitor app or enter their email and password on an ipad to sign in. The visitor recieves a push notification upon sign in as well as the host being visited. The host can view thier guests from within their app and sign out their guests when they leave. We capture a company/building's information such as location, opening times, staff, wifi code etc. What we are looking to do next is enable a chat feature where the company/building admin can enter even more info about their building such as "where can i get something to eat?, where can i get a coffee?, where are the restrooms?,Where are the emergency exits? , Shop directory, as so on. We would also like this to act as a help to the receptionist/admin who should be able to intervene any conversation at any time. If a visitor needs to ask the receptionist/admin something, she would be able to answer that visitor. So in a nutshell we are looking to build an AI Chat bot with machine learning to help a building admin handle questions related to their building/company. We need to let the admin populate all the specific info regarding their company/building so that the visitors can get relative answers about the building that they have scanned into. We are using the MERN stack.