Sign in with Microsoft 365 login account if you already are using Microsoft’s other services like Outlookcom, Xbox Live, Skype, or OneDrive, it means you can use this account for Microsoft Office 365 login.Microsoft365.com/setup
Go to Microsoft365.com/setup, Microsoft 365 Setup website.
Sign In to your Office Account or Create a New One.
Now Enter Product Key.
Click Install Office Button.
Go ahead and Click Install Office Again.
Save and Run office setup.
Wait for Office to finish Installation.