How to add a PDF form field (or a text) in the page bottom of a page of an existing PDF document using iTextSharp? Meanwhile,how can I make the PDF form field added (or the text added) link into another page using iTextSharp?

I have an existing PDF document named as aa.pdf. This PDF document has 3 pages. I'd like to add a PDF form field (or a text) at the page bottom of the first page in aa.pdf using iTextSharp.

Meanwhile, I also hope that the PDF form field added (or the text added) can link into another page of aa.pdf. For example, after I click the PDF form field (or the text) located in the first page of aa.pdf,this PDF document skips into the second page.

How can I realize the aboved functionalities using iTextSharp?

Thanks
...