How to set up variable equal to user input coordinate to draw a line

I am trying to draw a line using user input coordinate in window form application (WFA). The user will input array of points, and then I press the button to draw the connected point (line).

The code is simple and straights forward but I am struggle to image how I can use it in WFA, do I use textbox and insert the code in the textbox code? The following is the structure of the code, that's how I think it should be, any help please?

        using System;
     
    namespace Sample
    {
        class Test
        {
            public static void Main(string[] args)
            {
                string testString;
                Console.Write("Enter point1 coordinate - ");
                point1 = Console.ReadLine();
                Console.Write("Enter point2 coordinate - ");
                point2 = Console.ReadLine();
                
            }
        }
    }




private void Form1_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
{



 Pen redPen = new Pen(Color.Red, 1);

PointF[] ptsArray=
      {
            new PointF(20.0F, 20.0F),
            new PointF (20.0F, 20.0F),
            new PointF (200.0F, 200.0F),
            new PointF (20.0F, 20.0F)
      };

      e.Graphics.DrawLines (redPen, ptsArray);
           
           
           //Dispose of objects
            redPen.Dispose(); 
            
            
        PointF[] ptsArray=
      {
            new PointF(Console.ReadLine()),  // this is an example only
            new PointF (20.0F, 20.0F),
            new PointF (200.0F, 200.0F),
            new PointF (20.0F, 20.0F)
      };

      e.Graphics.DrawLines (redPen, ptsArray);
            
            
      
}