Sounds like you are on your way.
Unimportant stuff below.
iBooks, I should have just called it Books. It’s Apple’s book reading app. Not surprisingly, it reads the ePub format that Pages exports. Pages has an option to export directly to Books, if it’s installed
If you don’t have it, you can download it for free from the App Store.
Word for iPad will let you read docx files, even without an account. You just can’t edit or save them. On iPad Mini and iPhone you can get most of the features without an account. Microsoft has a strange rule about screen sizes of the device that determines whether you need a license or not.
Also, Pages will import Word files. It’s an acceptable way to read documents if you’ve no other way, or as a one time import of a document you want to modify and use. I con’t consider it good enough for collaboration. Errors tend to accumulate each time you pass the document back and forth between formats.