Program.cs

// See https://aka.ms/new-console-template for more information

using Syncfusion.Drawing;
using Syncfusion.Pdf;
using Syncfusion.Pdf.Graphics;
using Syncfusion.Pdf.Interactive;

//Create a PDF document
PdfDocument document = new PdfDocument();
//Add a new page
PdfPage page = document.Pages.Add();

//Create a Text box field
PdfTextBoxField textBoxField = new PdfTextBoxField(page, "FirstName");
//Set properties to the textbox
textBoxField.BorderColor = new PdfColor(Color.Gray);
textBoxField.BorderStyle = PdfBorderStyle.Beveled;
textBoxField.Bounds = new RectangleF(80, 0, 100, 20);
textBoxField.Text = "First Name";

//Add the form field to the document
document.Form.Fields.Add(textBoxField);

//Create a Button field.
PdfButtonField clearButton = new PdfButtonField(page, "Clear");
clearButton.Bounds = new RectangleF(100, 60, 50, 20);
clearButton.ToolTip = "Clear";
//Add button field to the form
document.Form.Fields.Add(clearButton);

//Create an instance of reset action
PdfResetAction resetAction = new PdfResetAction();
clearButton.Actions.GotFocus = resetAction;

//Create file stream.
using (FileStream outputFileStream = new FileStream(Path.GetFullPath(@"Output/Output.pdf"), FileMode.Create, FileAccess.ReadWrite))
{
    //Save the PDF document to file stream.
    document.Save(outputFileStream);
}

//Close the document.
document.Close(true);