Hi Moeen,
There are many information in these links:
stackoverflow.com/.../how-to-enable-create-insert-in-a-axgridview-in-enterprise-portal-dynamics-ax
www.slideshare.net/.../enterprise-portal-development-cookbook-ax-2012
www.axpulse.com/.../list-page-and-details-page-deployment-on-ax-2012-enterprise-portal