Microsoft Word or Apple Pages or any other word processing tool are fantastic for writing and formatting. When you format something in Word it adds a whole heap of code behind the scenes – stuff that WordPress hates!
So what this means is that we can’t just copy and paste directly from Word or Pages into a WordPress post.
What you can do though is use the “Paste as Text” button in the second line of the WordPress toolbar which strips out all the gunk and pastes clean text. Then you format it inside WordPress using Heading 1, Heading 2 etc and block text, bold, italics, bullet points, numbering, indentation, hotlines to other pages etc.