I was following a tutorial when creating a new worldspace.

I tried raising the land underneath the water but nothing happened. Then i realised it was because there is no land to edit.
Underneath the water is just a blank empty void. There is nothing to raise/lower

I thought it was just a problem with the worldspace i had created, so i opened a tamriel worldspace and found that also had an invisible ground/texture.

I'm really stuck here. Would appreciate the help
Thanks