In QuickBooks, you can save an invoice as a PDF file and later attach it to an email that you send to your customer.

Topline Portable Document Format files, or PDFs, are easily presented and exchanged across softwares—even Word—so here’s how to convert a PDF into a Microsoft Word document.

You can convert a PDF to a Google Doc if your PDF meets certain guidelines, like page orientation. If you want to convert it with the formatting, you'll need to have access to Microsoft Word.