// first page
Navigator.pushNamed(
   context,
   SomePage.routeName,
   arguments: {
      'v1': 'data1',
      'v2': 'data2',
      'v3': 'data3',
   },
)


// Second page
final arg = ModalRoute.of(context)!.settings.arguments as Map;

randomVar1 = arg['v1'];
randomVar2 = arg['v2'];
randomVar3 = arg['v3'];