The complete application (both admin & app) has been developed & built on Flutter. First, You have to install flutter on your computer. You can use Both Visual Studio Code & Android Studio as IDE for Flutter. The steps are the same for both IDE. We have used Visual Studio Code. So, Our Setup will be based on this IDE.
To install flutter on your computer, follow the official documentation from Google. Flutter Official Site: https://flutter.dev/.
You can follow these youtube videos to install flutter also.