I want to make a document template in MS Word?

In the pre-made templates from Microsoft, there are small grey areas that when clicked on, the already present text can be easily substitued with my own. How do I make these grey boxes?

I want to make a document template in MS Word?windows registry

I think you're referring to form fields. To use them, click View - Toolbars - and selec the "Form" toolbar.

If you mouseover the various buttons, it'll tell you what they are. The most common button (for my own use) is the first one - the text field. Click that button and it inserts a form field into your document.

Double-click the field and you can enter text to appear in the field until it's replaced by an actual entry.

Another good feature is locking the form. With the lock active, users can only fill in text in the fields and they can easily navigate from one to another by pressing tab or enter.