سلام توی ترمینال این پیام رو میده ، git هم در قسمت Environment variable مسیر فایل exe  مشخص شده 

Because pub global activate depends on flutter_gen any which doesn't exist (authorization failed), version solving failed.
Insufficient permissions to the resource at the https://pub.dev package repository.
You can modify credentials using:
    dart pub token add https://pub.dev