Firestore database is a non-relational database, unlike the traditional database (something like SQL) which is relational database. It means that it does not require a design of table structure.
Firestore database uses a document structure to store data, which is a collection of key-value pairs. Moreover, Firestore database is suitable for small and medium-sized applications, with real-time performance and easy-to-use APIs. It is one of the core services provided by Firestore database and can help developers quickly build real-time applications. In Realtime Database, data is stored in JSON format, making it easy for developers to store and retrieve data.
Here is a link of examples that how to store data. https://firebase.google.com/docs/firestore/manage-data/add-data And here is a YouTube video which demonstrate how to save data. https://www.youtube.com/watch?v=zpQle4SBRfg&list=PL4cUxeGkcC9itfjle0ji1xOZ2cjRGY_WB&index=4
Here is a link of examples that how to retrieve data. https://firebase.google.com/docs/firestore/query-data/get-data And here is a YouTube video which demonstrate how to retrieve data. https://www.youtube.com/watch?v=mYyPbfpoZeM&list=PL4cUxeGkcC9itfjle0ji1xOZ2cjRGY_WB&index=6