Can anyone please guide us ??

That page was added as part of support for "in-store pickup" functionality.  It displays orders that are not being shipped to an address but instead will be picked up by a customer at a designated location out of the stock that location has on hand (and most likely in the immediate future).  Those orders bypass the usual payment/release cycle used for shipped goods as the customer also can pay in person at the store.

Customers can designate the option to pick up at a store as part of the order process if the available stock meets the usual rules.  In Commerce Manager this is done with the "Pick a Fulfillment Option" drop down that has been added to the New Line Item configuration screen.  If you wish to make use of it with your front end site then you will need to implement your own approach, but you can see an example approach in the sample site.

Such orders appear immediately on the "Pickup Orders" page once they are placed and clicking on the information icon brings up a popup window with the specific line items needed so that the store staff can assemble the order.

We expect to iterate on the Pickup Orders page to provide more functionality in the future.  We are not currently supporting the additional data and messaging infrastructure needed to provide notification that a pickup is ready but that is an option as well.