Welcome!
I made this course in 2019 when I was first learning about voxel terrain. I've left it here since there are still people utilizing it as a reference (and it's free)
If you are interested in a more up to date course check out Make Minecraft - World Generation (Unity C# Jobs)
For just the basics though, I recommend my free introductory voxels course Make Minecraft in Unity - The Basics it has better explanations and covers things like:
- Block types
- Transparent Block types!
- Drag-and-drop terrain generator code system
But if your up for the old code base, or maybe looking for a planet terrain tutorial (which this course incidentally has) then go to section 3.3 :P see you there!