Firestore

Cloud Firestore (beta) is a fast, fully managed, serverless, cloud-native NoSQL document database that simplifies storing, syncing, and querying data for your mobile, web, and IoT apps at global scale. 

To connect Fire store, 

First step, is Authorization of user,  if you are  a authorized  user then you have to provide project id to connect Firestore. 

Please check documentation for create project.