Is there a free program like Microsoft Word?

Yes, several free programs do what Microsoft Word does: LibreOffice Writer (the most complete free desktop word processor: open source, offline, handles .docx well), Google Docs (free in the browser with real-time collaboration; the default choice if you mainly share documents), OneNote/Word for the web (Microsoft's own free browser version: genuinely free, lighter than desktop Word), and Apple Pages (free on Mac/iPad).

Honest trade-offs: complex Word documents (heavy tables, tracked changes across teams, macros) survive best in real Word. Conversions occasionally shift formatting in LibreOffice and Google Docs. For everyday writing, letters, reports and CVs, the free options are simply fine, and have been for years.

Quick picker: collaboration → Google Docs; offline power features → LibreOffice; already in Microsoft-land → Word for the web.