No you cannot file them all at once. If you have W-2 forms for previous tax years, you will need to file a separate return for each of the years to which the W-2 form applies. If you qualify, you can use TurboTax Free Edition for your 2018 but you will need to purchase prior year editions, but you will only be able to purchase prior TurboTax software back to 2015 (https://turbotax.intuit.com/personal-taxes/past-years-products/)
For tax years prior to 2015 you'll need to download the forms from the IRS website (https://www.irs.gov/)
