standard text formatting

Definitely don’t use Microsoft Word for that. WordPress is a standard HTML editor, but Microsoft Word is a word processor with a proprietary formatting language, something that WordPress tries its best to translate on paste, but there’s no guarantee it will get it right.

Stick to WordPress’s editor for formatting, and consider expanding the editor’s capabilities with a plugin like https://wordpress.org/plugins/tinymce-advanced/

If you really want to write your post first outside of WordPress, consider using a blogging client instead: https://codex.wordpress.org/Weblog_Client#List_of_Client_Software

You’re welcome!