Hello @armyanda92 -
For InVEST, it is not necessary to have the land cover description in the raster. It certainly makes it easier to use if you work with a GIS program like ArcGIS that supports raster attribute tables, but programs like QGIS very unfortunately don’t support raster attribute tables at all. Since you do use ArcGIS, you can add a column with the description to the raster attribute table yourself.
The model does not output the amount of export and retention by land cover, but you can use a GIS tool like Zonal Statistics to easily calculate this.
~ Stacie