I want you to go ahead and convert the example from the VA (Vertex Array) section to use a VBO (Vertex Buffer Object) and an IBO (Index Buffer Object) to render.
You will only have 4 member variables: the grid, a vertex buffer handle, an index buffer handle and an integer containing how many indices to draw (size of the index buffer).
Take the current global arrays and make them local to initialize. The final image should look the same.