How to display Fields and Visualization in Power BI Online

In the Power BI Desktop in Report View, there are three panes on the right; the Filter, Visualization, Fields Panes.  Fields is also seen in the Data and Model views.

However, when I publish a report (tab) and view it in Power BI Online (through a browser), the Visualization and Fields panes are not seen.  How do I display them?

Thank you.