State management is Provider + ChangeNotifier .
You can choose branch textField and textFormField.
I wrote the article in Japanese → Flutter で TODO アプリ📝 を作ってみた！ - Qiita
This project is a starting point for a Flutter application.
A few resources to get you started if this is your first Flutter project:
For help getting started with Flutter, view our online documentation, which offers tutorials, samples, guidance on mobile development, and a full API reference.