Penalties for filing late are based off of the amount that is still owed on the original due date. So if you get a refund each year, the penalty is based off of zero or a negative number and generally there is no penalty. As for receiving a refund, the IRS only allows refund claims for up to three years after the original due date. However, in some instances this limited period can be extended due to federally declared disasters. You can however file missed tax returns for up to 6 years, including the most current year open for filing. This might be done if you want to show "current" with filing, even though some of the years are past the date to receive a refund.
TurboTax can be used to file prior year tax returns, but only the TurboTax Desktop product. https://turbotax.intuit.com/personal-taxes/past-years-products/
Although older versions may be still available through outside vendors, Intuit only supports three prior years of tax software. The current year (2024) return can be filed using either TurboTax Desktop or TubroTax Online. The three years prior to that (2023, 2022, 2021) can be found using the link above.
As for the forms required, the software will produce the tax forms that need to be filed. These are generated from you inputting your tax information (such as info from a W2, 1099, 1098, etc). If you need to locate those documents, the best place to start is by creating an online IRS account and requesting a Wage and Income Trnascript.
