office.com/setup: Without activating the MS Office setup, you won’t be able to access its features. To do so, follow these steps:
Once you are done with the downloading and installation, go for activation
For this, click on the Microsoft Office icon and you will be prompted to an Office Activation Wizard
Enter the office setup product key, if required
Follow the on-screen instruction to finish the activation process
Your MS Office is ready to use!