How to add a border in an image with C #

I was able to solve this problem by concatenating two images.

            Image principal = Image.FromFile(@"ImagemPrincipal.jpg");
            Image logo = Image.FromFile(@"ImagemHeader.jpg");

            int imagemSaida_Width = principal.Width;
            int imagemSaida_Height = principal.Height + logo.Height;

            var imagemSaida = new Bitmap(imagemSaida_Width, imagemSaida_Height);

            using (principal)
            {
                using (imagemSaida)
                {
                    using (var canvas = Graphics.FromImage(imagemSaida))
                    {

                        canvas.InterpolationMode = InterpolationMode.HighQualityBicubic;
                        // Definir plano de funda do arquivo de saida como Branco
                        canvas.Clear(Color.White);

                        // Adicionar o logo no arquivo de saida
                        canvas.DrawImage(logo, 0, 0);

                        // Adidionar principal no arquivo de saida
                        canvas.DrawImage(exame, 0, logo.Height);
                        canvas.Save();
                    }
                    imagemSaida.Save("ImagePrincipalComLogo.jpg");
                }
            }

Hello, would you just change the sizes of the border's px no?!

border-image-width: 10px 10px 10px 10px;
          (top) (right) (bottom) (left)