A family of Microsoft word processing software products for creating web, email, and print documents.
In the meantime, I suggest trying an Online Repair to thoroughly repair any issues with the Office installation:
In the search bar, type Control Panel > Programs and Features > find Microsoft 365/Office > right-click it > select Change > then run Online Repair.
If the issue persists, please answer the following questions to help determine what may be causing the problem:
1. What changes did you make to your computer or subscription before the issue started?
2. What exact error message you get everytime you open Word or Excel?