How to find overlap polygon in same layer

Question

 

 

Visual strategies for overlapping polygons 

https://www.esri.com/arcgis-blog/products/arcgis-pro/mapping/visual-strategies-for-overlapping-polygons/

 

ESRI document,   intersect 

https://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Intersect/00080000000p000000/