Александр Юдаков

using Newtonsoft.Json;
using System.Diagnostics;
using System.IO;

namespace ConsoleApp1
{
    public class NickNamePair
    {
        [JsonProperty("nickname")]
        public string NickName { get; set; }
        [JsonProperty("record")]
        public int Record { get; set; }

        public override string ToString()
        {
            return $"{NickName} {Record}";
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            using var stream = new StreamReader("data.json");
            var myJson = stream.ReadToEnd();
            var realresp = JsonConvert.DeserializeObject<NickNamePair[]>(myJson);
            foreach (var item in realresp)
                Debug.WriteLine(item);
        }
    }

}