I'm not really sure what the Learn account is. Is it this? If your login through the Learn account gives you Editor, Field Worker, Creator, or a GIS Professional type, that'll be enough to get you a Basic license when you log in and license the Runtime as described here.
But if you are just doing some R&D and developing (rather than deploying an app into production) then you can just not license the app at all and it'll run in development mode. This will display a watermark on any map view, but you can try out all the Runtime APIs.
Does that help?