is it possible to set group template fro pallet?
consider the following diagram is it possible to drag a node from pallet say entity but when it is dropped on the diagram dive it produces a group like the Entity1 or Entity2

i was using the template in pallet from diagram div but now i need it to look better

Yes, a Palette is just a Diagram with a few properties set. So you can set the Palette.groupTemplate or Palette.groupTemplateMap and have the groups appear however you like.

As GoJS Palette -- Northwoods Software shows, the same data can look different in different diagrams.