When the OP says Edit I think you will find he means edit the text he
has scanned in but has not run through an OCR application to turn it
into editable text. IOW to change fonts or individual words or
spellings; to substitute his business name for the one in the document
he has "borrowed" -- he should think about copyright law, in case ...

As you say you can edit an image as an image but that is not often very
useful in scanning say a document for reuse.