Generally if you scan a document you are basically just taking a picture of it so the text will not be editable in word.
If you can get the text into word then you are using OCR (optical character recognition) which will attempt to read the text and recreate it for you, but most OCR programs are limited and they will often muck up any formating, won't deal with text wrapping around pictures well and often make mistakes with the text.
What do you intend to do with the scan? if you just want to print it or send it to people then you'd be better off scanning it as a PDF if your software supports this. If you want to edit it then it will be tricky.