Hi Sayali,
What you need is that add more columns to following cas list in the portal, right?

If so, you can go portal management app, navigate to Entity list and open 'Customer Service-Case List', three views has added.

So go Settings > Customizations > Customize the system > Entities > Case > Views.
Open one view that showed in the list(for example:Web-open cases), then add columns you want, save and publish.

Test:

For second question “automate the status of case in portal”,What does this mean?
From aboved screenshot, 'Status Reason' field has added to the view.
Regards,
Leah Ju
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