ArcGIS Pro 2.7 API Reference Guide
GroupLayer Class
Members 

ArcGIS.Desktop.Mapping Namespace : GroupLayer Class
Represents a layer containing an editable collection of layers.
Object Model
GroupLayer ClassLayer ClassCIMDataConnection ClassCIMBaseLayer ClassSpatialReference ClassMap ClassILayerContainer InterfaceEnvelope Class
Syntax
Remarks
To create a GroupLayer, you must call CreateGroupLayer() method of the LayerFactory class, instead of directly using a constructor.
Inheritance Hierarchy

System.Object
   ArcGIS.Desktop.Framework.Contracts.PropertyChangedBase
      ArcGIS.Desktop.Mapping.MapMember
         ArcGIS.Desktop.Mapping.Layer
            ArcGIS.Desktop.Mapping.CompositeLayer
               ArcGIS.Desktop.Mapping.GroupLayer

Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

GroupLayer Members
ArcGIS.Desktop.Mapping Namespace