Create the text box you want. Save it as AutoText or as a Text Box Building Block. (I think AutoText would be better because you can use a shortcut to insert.) To save an AutoText entry (or other building block) in a template, select it and press Alt+F3.
Automated Boilerplate Using Microsoft Word

If you name your AutoText entry "mytb" you will can type, as a separate word, "mytb" and press the F3 key to create another text box for you to type in. That text box will be anchored to the paragraph you were in when you pressed F3.