Second Scene Terrain or Create Neighbor Terrain

I understand the reason for making a terrain in a second scene for the upcoming lessons on loading scenes which is vital to know. However, I was working about the Create Neighbor Terrain tool in the Terrain component. Is this a good option for making an overworld, then using different scenes for things like dungeons or inside buildings? If so, does anyone know if unity automatically optimizes the loading in of neighbor terrains (only loading in those they player can see for example)?

What you’re talking about is called level streaming. This is a bit complicated, as you essentially do most of the work to stream the levels as needed. It’s beyond the concepts we’re teaching in this course, but there are some excellent tutorials out there for managing these.