I page compatible with Word?

Pages was never written to be a Word clone. Thus, you can open a Word document and Pages will translate it into Pages internal (.page) document format. Features used in Word that are not supported in Pages will not be translated (dropped), and font references in the Word document that are not physically installed on the Mac will be replaced via font substitution. The original Word document remains unchanged.

To get the Pages document back to Word .docx, one must export and undergo another document translation which if there are Pages features not used in Word, then those will be dropped from the exported document.

What this spells is that if you must exchange Word documents with others using Word, then use Microsoft Word. It will save you a lot of grief because you are always working in the native Word document format without the roulette of translation.