In ArcMap, you can show the geographic extent of one data frame in another data frame. So, for example, you can create a layout containing two data frames, the main map - and an inset overview map depicting a rectangle for the extent of the main map.
Can this be done in ArcGIS Pro?
In ArcPro, you can link maps so you can view the same extent of each map simultaneously. But, is there a way to mark the extent of one map in another map?