Anne-Marie Concepcion has the best videos on bringing Word files into InDesign that I have seen.
She talks about how to clean up Word files and (at the end) references Word macros which might help:
Lynda.com has a 10-day free trial.
If you really only need to change the font, don't bother about setting up and applying correct styles for everything. Use "Type > Find Font ..." and change them one at a time.
I believe this is ever so slightly safer than 'select all' & changing the font for all text. First off, "Select All" does not - despite of its name - really select all text. It only works on a single spread (when the text cursor is not inside a frame) or continuously thread story (with the text cursor in text). It will skip nested frames, table contents, and footnotes. In addition, there may be any number of weird fonts used for bullets and special symbols.
Picking just the 'plain text' fonts off one by one with Find Font has none of these drawbacks. A further advantage is that you get to see what else is used in the document, so you can check if bullets etc. also may need changing, or can be left as they are.