There is more than one way to make a mesh. You can use a Unity primitive. You can make a mesh outside of unity with tools like Blender or Magicavoxel. Or... you can procedurally generate a mesh through code in Unity using scripts. When you procedurally generate a mesh there are some benefits. You can do things like the voxel worlds of Minecraft and more. In this Unity tutorial we will make the simplest mesh (a triangle) all the way up to a cube mesh using C# scripts. We will see how to specify the vertices, triangles, and uv coordinates for materials (textures). And we will understand how to specify to Unity which side of the mesh polygons to render and which to not (backface culling)
YouTube: https://youtu.be/AuwEG1h2xPg