How to rotate pages in a PDF file?

using Syncfusion.Pdf;
using Syncfusion.Pdf.Graphics;
using System.Drawing;

Imports Syncfusion.Pdf
Imports Syncfusion.Pdf.Graphics
Imports System.Drawing

//Create an instance of PdfDocument
using (PdfDocument document = new PdfDocument())
{
 //Add a section
 PdfSection section = document.Sections.Add();
 
 //Rotate a section or page
 section.PageSettings.Rotate = PdfPageRotateAngle.RotateAngle90;
 
//Add a page
 PdfPage page = section.Pages.Add();
 
 //Create PDF graphics for a page
 PdfGraphics graphics = page.Graphics;
 
 //Create a solid brush
 PdfBrush brush = new PdfSolidBrush(Color.Black);
 
 //Set the font
 PdfFont font = new PdfStandardFont(PdfFontFamily.Helvetica, 14);
 
 //Draws the text
 graphics.DrawString("Rotated by 90 degree", font, brush, new PointF(20, 20));
                
 //Save and close the document
 document.Save("Output.pdf");
}

'Create an instance of PdfDocument
Using document As PdfDocument = New PdfDocument()
   'Add a section
   Dim section As PdfSection = document.Sections.Add()
 
   'Rotate a section or page
   section.PageSettings.Rotate = PdfPageRotateAngle.RotateAngle90
 
    'Add a page
    Dim page As PdfPage = section.Pages.Add()
 
    'Create PDF graphics for the page
    Dim graphics As PdfGraphics = page.Graphics
 
    'Create a solid brush
    Dim brush As PdfBrush = New PdfSolidBrush(Color.Black)
 
    'Set the font
    Dim font As PdfFont = New PdfStandardFont(PdfFontFamily.Helvetica, 14)
 
    'Draws the text
    graphics.DrawString("Rotated by 90 degree", font, brush, New PointF(20, 20))
 
    'Save and close the document
    document.Save("Output.pdf")
End Using