I am trying to recreate the functionality of a NodeType/Node entity at a basic level.

I want to define entity types (FooType) which can be fielded individually, just like NodeType can be.

I used the Drupal Console to generate a config entity and content entity. Out of the box, it creates types and content entities of those types. However you can't field those types, I don't see a way to add that.

When I try to mimic the annotation in NodeType to allow fields, I get the following error when I try to save a field to a FooType:

    Missing bundle entity, entity type foo_type, entity id foo.

Where am I going wrong? Is this something the Drupal Console can already do and I missed it?