Recently did a Dynamo course and was instructed to Create Group under the Edit tab for a selection of nodes, also named them but don’t know how to recall them when needed.
There is no way to recall a group of nodes. Grouping nodes does not make a set group instance like it would with elements in Revit. It is mostly just for organization and keeping the screen looking clean. It has no other function than that.
Copy / Paste does work though