And for data environment, you are able to find it in two location, 1 is by right click on the customization layout, another is through File, on the top menu bar.
By right click on the report layout, the panel shown will be blank by default.
As for Data Environment from File, all the data fields and its data type related to the particular report will be shown. By selecting a data field and clicking Browse, it will show you the data table of the field.