If you are asking about preparing and filing a tax return for a prior year, you can buy and download TurboTax for the year that you want to file back to 2013. Here is a link: https://turbotax.intuit.com/personal-taxes/past-years-products/
Prior year returns must be printed and mailed. They can't be efiled.
You could also download the forms from the IRS for the year you want to file and fill them out by hand: https://www.irs.gov/forms-pubs