I have drawn a polygon in ArcGIS Pro 1.3 now I want to calculate its area
You need to use the* Geoprocessing* tool, Add Geometery Attributes. This
tool will add a column at the end of your attribute table with the desired
area calculation. You need to specify the projection to use in the area
And the help document for that Add Geometry Attributes—Data Management toolbox | ArcGIS for Desktop
But out as Dan mentioned, if a graphic that will not work unless it us converted if saved to a shape or feature class, if you want the info saved, although you could use the measure tool fir a one-off estimate. Measure—ArcGIS Pro | ArcGIS for Desktop
you may want to see if any of the tools Jenness Enterprises - ArcGIS Tools; Tools for Graphics and Shapes will work (I have not tried). They look to be written for Desktop, but if in a toolbox, may work with pro.
If it is a feature in a geodatabase, a Shape_Area field would automatically calculated. If it is a graphic, no area will be calculated.
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