The diagram type doesn't matter for transformations, but you can change it in the Diagram menu under Advanced. What you've drawn here, a set of database tables, should be in what EA calls a Data Modeling diagram.
Regarding transforming to a source code model, you won't get very far with EA's built-in transformations. You can transform your data(base) model to an Entity-Relationship Model or to a DBMS-specific model, but that's it. If you want to transform to an implementation-language model, you'll have to write your own transformation.