To protect your document workbook or exct in excel.
you first have to go to the review tab on the ribbon.
you then go to the changes group and click any button that says protect depending on what do you want to put a password on after you will have all the options on what specifically you want to protect.
First go to the to the Microsoft button and then click. After scroll down to the prepare click and then go to the inspect button when it opens. You will then have the options on what you want to inspect.