"Editer or Prévisualisation"

Hello,

In a previous message, I explain that I don't fond the option "Editer or Prévisualisation" in all of my documents. Now, I see that this "problem" is present only with documents that I charge from Word Office.
With the documents that I create directly in Zoho, I have the possibility to find "page set up" with "Editer".
Is it just and normal?

Thank's for your help.

Michel