I am new to Unity and Dots, but I think what you want is called the “Chunk”. You will need to go hunt for the api on how to do that. I saw it before 2 weeks or so ago when I was a total noob. You will need the entity for each thing you want to update too, so you can offset to the right location in the chunk.
I found 2 posts that seem pretty useful starting point for chunk research:
https://discussions.unity.com/t/721477/8
https://discussions.unity.com/t/717045/2
Hope that gives you a starting point to research more. If you get it solved, please post a code snippit! I’d like to know the solution.