最简单

namespace ProcessStu01
{
    internal class Program
    {
        static void Main(string[] args)
        {
            for (int i = 1; i <= 100; i++)
            {
                Console.Write("\r{0,3}%",i);
                Thread.Sleep(50);
            }
        }
    }
}

第三方库

https://github.com/Mpdreamz/shellprogressbar

using ShellProgressBar;

namespace ProcessStu01
{
    internal class Program
    {
        static void Main(string[] args)
        {
            Console.ReadKey();
            const int totalTicks = 100;
            var options = new ProgressBarOptions
            {
                ForegroundColor = ConsoleColor.Yellow,
                ForegroundColorDone = ConsoleColor.DarkGreen,
                BackgroundColor = ConsoleColor.DarkGray,
                BackgroundCharacter = '\u2593'
            };
            using (var pbar = new ProgressBar(totalTicks, "showing off styling", options))
            {
                for (int i = 0; i < totalTicks; i++) 
                {
                    pbar.Tick();
                    Thread.Sleep(100);
                }
            }
            Console.ReadKey();
        }
    }
}