create me a tutorial on how to use dialog flow and Firebase

i need an easy to follow tutorial on how to just read from a Firebase database using Dialog flow. i want to create 4 intents which return 4 different things. intent 1. How many products were sold today. return Count. intent 2. list of top ten customers by sales return list intent 3. number of orders today return count intent 4. Total number of active customers return count all