Overflowed error in a container

You are working with a fixed size container, if the information is variable it may not always look good, you could change to a wrap like this.

return Container(
    width: 500.0,
    height: 600.0,
    child: Wrap(
      children: [
        Container()
      ],
    )
);

What is happening is that you are giving measurements in pixels within the column that are exceeding the limits of your Container, so it is clear that if you have a 200ml glass of water and you put 250ml of a small part of it, it will spill.

This can be selected with Expanded and Flexible, but from what I see of your application I recommend that you start using a ListView or a CustomScrollView so that you don't have these relative measurement errors.

import 'package:flutter/material.dart';

const Color darkBlue = Color.fromARGB(255, 18, 32, 47);

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.dark().copyWith(
        scaffoldBackgroundColor: darkBlue,
      ),
      debugShowCheckedModeBanner: false,
      home: const Scaffold(
        body: Center(
          child: MyWidget(),
        ),
      ),
    );
  }
}

class MyWidget extends StatelessWidget {
  const MyWidget({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Container(
      width: 500.0,
      height: 200.0,
      margin: const EdgeInsets.symmetric(horizontal: 5.0),
      decoration: const BoxDecoration(
        borderRadius: BorderRadius.all(Radius.circular(8.0)),
        color: Colors.purpleAccent,
        boxShadow: [
          BoxShadow(
            color: Colors.black,
            blurRadius: 0.0,
            spreadRadius: 0.0,
            offset: Offset(0.0, 0.0), // shadow direction: bottom right
          )
        ],
      ),
      child: Container(
        margin: const EdgeInsets.symmetric(horizontal: 15.0, vertical: 20.0),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Expanded(
              flex: 5,
              child: Container(
                margin: const EdgeInsets.only(top: 11.0),
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    Image.network(
                      'https://images.unsplash.com/photo-1616436348354-77e70e18226e?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=764&q=80',
                      width: 50,
                      height: 50,
                    ),
                    const Flexible(child: Icon(Icons.favorite, color: Colors.red)),
                  ],
                ),
              ),
            ),
            const SizedBox(
              height: 10,
            ),
            const Expanded(
              flex: 2,
              child: Text(
                'Netflix',
                style: TextStyle(fontSize: 12, fontWeight: FontWeight.bold, color: Colors.white),
              ),
            ),
            const Expanded(
              flex: 3,
              child: Text(
                'Front end',
                style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold, color: Colors.white),
              ),
            ),
            const Spacer(),
            Expanded(
              flex: 2,
              child: Row(
                mainAxisAlignment: MainAxisAlignment.start,
                children: const [
                  Icon(
                    Icons.location_on,
                    color: Colors.white,
                    size: 15,
                  ),
                  Text(
                    'Mexico',
                    style: TextStyle(fontSize: 12, fontWeight: FontWeight.bold, color: Colors.white),
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }
}