No problem 
Data assets and asset registries are useful to use when you want to load groups of assets. Not sure how to explain it succinctly, so I would recommend researching them as well and see how you can use them in your project.
There are many was that you can structure your project. If you want your project to be modular, you might want to use components or data assets. If it is a small project, you might want to keep it cohesive with just few classes or maybe you can combine different ways to implement features. You can use inheritance, components, interfaces, singletons like a game instance, function libraries, data assets/registries or any other tool to structure your project, so it is the most readable, performant and optimized. For more abstract understanding of this I would suggest reading about design patterns.