Hi Swati,
1) For creation of olap connection to dashboard go through this link http://scn.sap.com/docs/DOC-22040
2)Net weaver BW connection to dashboard go through this http://www.sdn.sap.com/irj/scn/go/portal/prtroot/docs/library/uuid/0092bfd7-5958-2e10-1885-900f5e286594?QuickLink=index&overridelayout=true&50903952495825
3) Create a new olap connection in IDT. By this way you can access the queries in dashboard.
4) Yes you can bind directly to component go through this http://scn.sap.com/docs/DOC-21260
Hope this helps.
Thanks&Regards,
Krishna