In this tutorial, we take a closer look at the relationship between components, entities, and prefabs in the scene graph system. On the surface, it is simple, but practically speaking, it can be confusing initially.
https://dev.epicgames.com/community/learning/tutorials/3JoR/fortnite-components-vs-entities-a-closer-look-at-the-prefab-scene-graph-example-in-uefn