Hi Yahya,
Thank you for using Syncfusion Products.
Currently we don't have support to insert the form fields in the PDF document Header part. We have logged feature request regarding this. But we can create such document without inserting in header part.
Please refer the below custom sample which is used to create document like the attached image:
http://files.syncfusion.com/samples/DocIO.Windows/I55474/main.htmPlease try this and let us know if you need any further assistance.
Best Regards,
Bhuvana