If whoever did your taxes before used TurboTax, then the easiest way to file an amended return would be to get the file from them if possible, and open it in the correct TurboTax software for the year. If you can't do that, when you amend the returns you'll have to re-enter all the information from the return. If you need prior year software, you can get it here: https://turbotax.intuit.com/personal-taxes/past-years-products/