Program.cs

using System;
using System.Threading.Tasks;

namespace test
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Starting...");
            MainAsync().GetAwaiter().GetResult();
        }

        static async Task MainAsync()
        {
            bool isDone = false;

            Task.Run(async () => {
                Console.WriteLine("Task1 started");
                
                while (!isDone) {
                    await Task.Delay(1);
                    Console.WriteLine("Inside Task1: " + isDone);
                }

                Console.WriteLine("Task1 finished");
            });

            await Task.Run(async () => {
                Console.WriteLine("Task2 started");
                
                isDone = false;
                await Task.Delay(10);
                isDone = true;
                
                Console.WriteLine("Task2 finished");
            });
        }
    }
}