Hi Vinita,
We can add field to UI both header and item without modifying WD component using customization. Please follow the below paths,
For adding fields to UI:
spro->SAP supplier relationship management->SRM server->Cross-applications basic settings->Extensions and field control->configure field control->configure control of fields on header/item level->metat data on header or item-> here u have to give the field name, business objects and can control the visibility in UI. U can also make use of dynamic class to change the properties dynamically.
For moving added fields to different cntainers:
spro->SAP supplier relationship management->SRM server->Cross-applications basic settings->Extensions and field control->configure generic field display on user interface
heare u can change the sequence of fields to be dispalyed in UI, container in which field should be added and alignment.
Thanks
Jixon