through a web browser by signing in at Office.com with a Microsoft account. Microsoft 365 Education:
Unlike Microsoft 365, it does not receive new feature updates, only security patches and quality fixes. The Risks of "Free" Product Keys through a web browser by signing in at Office
There are no legitimate "free product keys" for Microsoft Office LTSC Professional Plus 2021. Any website offering such keys is likely distributing stolen, counterfeit, or trial keys that will either not work, stop working after a short time, or could expose your computer to malware and security risks. stop working after a short time
