PDF files are not meant to be edited. Although you can do some minor editing to a pdf file using one of adobe acrobat commercial applications, but for series editing you need to go back to the source document, edit it, then convert it back to a pdf file.
That said, you can load pdf files into Word but they will load as an image. To do that open Word, click Insert > Object > 'Create from File' tab, then browse to your file to select it.
Hope this helps. Let me know if you have any questions.
Was it the free "Adobe Reader" or the commercial "Adobe Acrobat" that you have downloaded from adobe?