Thanks for the link. I am reading it for better understanding.
I just came to know from SR that, In order to see the BI Publisher in the Presentation Server list of values, we have to embed the BI Publihser report inside an OTBI Dashboard.
So we need to create a 'Dashboards' folder (It is must only then we are able to see it via fusion apps. to select and embed), then Dashboard and add the desired report to this dashboard. Now we can navigate to this dashboard, open it and select the page to embed it.
Might be useful for the ppl who faces similar issue. Thanks.