how to give width based on screen size flutter

double height = MediaQuery.of(context).size.height;
double width = MediaQuery.of(context).size.width;

double width = MediaQuery. of(context). size. width;
double height = MediaQuery. of(context). size. height;

double height = MediaQuery.of(context).size.height;

import 'package:flutter_screenutil/flutter_screenutil.dart';

dependencies:
  flutter:
    sdk: flutter
  # add flutter_ScreenUtil
  flutter_screenutil: ^0.4.2