using System;

public class Program

{

    public static void Main()

    {

        string settingFromDatabase = "{\"_MINIMUMPENDTHRESHOLD\": \"2\", \"USEFAKE\": \"true,false\", \"UseFakeTinCheck\": true}";

        var settings = System.Text.Json.JsonSerializer.Deserialize<TaxpayerIdNumberUnderwritingSettings>(settingFromDatabase ?? "{}");

        Console.WriteLine($"UseFakeTinCheck: {settings.UseFakeTinCheck}");

        Console.WriteLine($"MinimumPendThreshold: {settings.MinimumPendThreshold}");

    }

}

​

public class TaxpayerIdNumberUnderwritingSettings

    {

        public bool UseFakeTinCheck { get; set; }

        public string MinimumPendThreshold { get; set; }

    }