Show Notification by new article published

Hello,
How can I read JSON file and show notification when new article published?

Read this
Write: JS function for parse JSON --> function that compares old and new news --> notification fucntion --> Toast framework7 function

hello,

but i need native notification.like WhatsApp when recive new message

You need more expanded like Cordova to access the export for OS

Use phonegap plugin push

Or use Firebase Cloud Messaging for web app web push https://firebase.google.com/docs/cloud-messaging/js/client It has detailed documentation on how to implement it in app. But it also will required server-side

hello,
does it show notification when application is cloesed?

Firebase - Yes
phonegap plugin push - yes, but there are exceptions