Hi Rajesh,
The error message indicates that the federated Server site you're trying to configure to become a hosting server for your Portal instance does not have the ArcGIS Data Store installed. You need to install the ArcGIS Data Store and configure it with your federated Server site. Then you can select it to be a hosting server for Portal.
Configure a hosting server—ArcGIS Server Administration (Windows) | ArcGIS Enterprise
Hope this helps,