WorldClock.cs

using System;
using System.Net.Http;
using UnityEngine;

/// Go to https://github.com/JamesNK/Newtonsoft.Json/releases and add the
/// appropriate Newtonsoft.Json.dll to your Assets/Plugins folder.
using Newtonsoft.Json;


public class WorldClockTime
{
    [JsonProperty ( "currentDateTime" )]
    public DateTime CurrentDateTime { get; set; }

    [JsonProperty ( "currentFileTime" )]
    public long CurrentFileTime { get; set; }
}


public class WorldTime : MonoBehaviour
{
    static HttpClient client = new HttpClient ( );

    // Start is called before the first frame update
    void Start()
    {
        GetTime ( );
    }


    private async void GetTime()
    {
        try
        {
            var response = client.GetAsync ( "http://worldclockapi.com/api/json/utc/now" );
            var result = await response;
            var responseString = await result.Content.ReadAsStringAsync ( );

            //Log ( $"PostAsync<T> result.StatusCode : {result.StatusCode} {responseBody}" );
            if ( !string.IsNullOrEmpty ( responseString ) )
            {
                var currentTime = JsonConvert.DeserializeObject<WorldClockTime> ( responseString );

                var date = new DateTime ( currentTime.CurrentFileTime );

                Debug.Log ( $"Current UTC time is {currentTime.CurrentDateTime}.\n" +
                    $"Current Local Time is {currentTime.CurrentDateTime.ToLocalTime ( )}\n" +
                    $"Current UTC CurrentFileTime is {date}.\n" +
                    $"Current Local CurrentFileTime is {date.ToLocalTime ( )}" );
            }
        }
        catch ( Exception e )
        {
            Debug.LogWarning ( $"Exception! {e.Message}" );
        }
    }
}