Can we use Talend open studio community edition for reporting purpose? I mean something similar to a tableau or shiny dashboard hosted in a website?
Since reporting is simply calculating and displaying data, yes you can....kind of. You can prepare your data using Talend and even write dynamic web content using Rest service functionality....although that might be a little harder than using a tool meant for that purpose. What you are asking is possible, but I would look into some open source reporting tool and look at how you can use Talend with that tool. That will certainly be possible.
So i assume there isn't anything available in Talend, although we can integrate Talend with some other application to display results in a website.
Just as examples of real use:
1) we are use Talend for prepare data from different sources, than by REST (or by tJasper* components) call jasper Server for prepare reports and send eMail notification.
2) second way - REST services in ESB runtime. Applications call service and use response data.
It's not similar with Pentaho, but also work