using System;

using System.Text.Json;

using System.Net.Http;

using System.Threading;

using System.Threading.Tasks;

public class Program

{

    public async static Task Main()

    {

        var p = new Program();

        using var cancelSource = new CancellationTokenSource(TimeSpan.FromSeconds(3));

        Console.WriteLine("Start task");

        p.Execute(cancelSource.Token);

        p.Execute(cancelSource.Token);

        await Task.Delay(5000);

    }

    public async Task Execute(CancellationToken cancellationToken)

    {

        while(!cancellationToken.IsCancellationRequested)

        {

            Console.WriteLine("waiting...");

            await Task.Delay(1000);

        }

        Console.WriteLine("Task Cancelled");

    }

​

}