Copy contents like subgroups, blog and forum application from one group to another group

Howdy Brindha - Today there is not an option to copy subgroups or forums from one group into another group. Blogs, however, can be used to share content across groups. Details can be found in the following video: Sharing Content Across Groups 

For a group in the Group Options you can change the parent group, the same applies to applications, see their corresponding options. 

Thank you Tom Paolucci 

Thank you Patrick M. But I do not want to move it completely, instead want to copy contents to new group. 

Then no there is no copy functionality, only move.