Hi Venu,
You may search for the "Service Portal" plugin amongst the list of available plugins and then activate/upgrade link/URL, this shall make the Service Portal application visible.
If you have upgraded and are activating the Service Portal for Enterprise Service Management plugin, the following plugins are also automatically activated as a part of the Installation process:
Service portal: Service status
Service Portal configuration pages
Service Portal Designer
Service portal Social QA
Service portal surveys
Regards,
Mishu
