If you are seeking to edit your own web pages, you will want to use an HTML and CSS editor.
Microsoft Word is not that.
Current Word can save an HTML document. When doing that, I’d strongly recommend verifying the generated HTML for standards compliance.
Decades-old versions of Word could read then-current HTML. Sort of. But that all ended sometime back around Word 2002 or so, maybe a few versions later.
For HTML and CSS editors, among various other options, there is Adobe Dreamweaver. RapidWeaver is one of the other alternatives listed there, though Realmac is replacing RapidWeaver classic with RapidWeaver Elements. Among the other HTML editors, I’ve used Dreamweaver and Sparkle, and both work. I’ve also used an older version of the Composer HTML editor, which is now part of the (free) SeaMonkey suite.