Hello! I have recently started using ArcGIS Pro after originally learning on ArcMap.
To export data in ArcMap I would just right click on the layer and select Export Data --> All features in view extent or selected features.
From what I can find it is a similar process in ArcGIS Pro. Right click on the layer, select Data --> Export Features, then under the Environment tab select the extent as "current display extent", etc.
This all seems to work how I would like it - the attribute table for the new layer only lists the fields I selected and the map only shows the layers selected. But under the Contents pane, all the original fields are listed under the layer, and therefore all get listed in the Layout Legend.
Am I missing a step?