Joining Tables
Sometimes you are able to find a spatial dataset on a topic (e.g. polygons of US states), but its attribute table does not contain much useful information. If you have a table with your desired information (e.g. population per US state), you can join it to the spatial dataset using a common field between the two (US state ID number or name).
Check out the following handout for instructions on how to join tables in ArcGIS Pro: