This may seem a silly question, but have you installed your purchase?
When you open Word are there ads on the right side? If so, what you are seeing is the Starter edition.
If you right-click on the ribbon, you should see options to customize the ribbon.
Note: You’ve posted your question or problem in response to a question that has already been marked as “answered” by the original poster. Your computer and Word configuration is unlikely to be the same as that of the original poster.
Posting this way means you may not get as good a response as you would if you started a new question.
The reason for this is that people answering these questions look for ones that haven’t already been marked as having been answered.