A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data
Hello @SRIKALYANI M
Read-only mode normally means Office is installed but doesn't currently have a valid activation/license.
Since this appears to be an Education account, first sign in to Microsoft 365 using your school/university account and check whether your institution still provides a Microsoft 365 license that includes the desktop Office applications. Some Education licenses provide web apps only.
On the iMac, open Word → Sign Out, close all Office applications, reopen Word, and sign in using the same account that owns the license. Microsoft also provides a Mac license-removal tool if an old or incorrect Office license is cached.
If your school no longer assigns you a desktop-app license and you're unable to purchase one, you can still use Word, Excel, and PowerPoint for the web with an eligible Microsoft account, although they have fewer features than the desktop applications.
If you share the exact activation message shown under Word → About Word/Account, we can narrow down whether this is an account, license-assignment, or cached-activation issue.
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