Whatsupp chat bots anyone got experience

I am playing with a concept to expand my Iot business and looking at a whatsupp or similar chatbot. Basically I whant the client to ask it a question with key trigger words and have it reply with the result. example a user could message "temperature of oven" and it would reply "oven is 230 c"

The information and technical abilities I have, but it seems like I need a bot whatsupp gateway. Anyone know of how to approach this. Any guids on how to make a bot?