Yes, you can still file a tax return for 2019, but if the return shows that you are due a refund then you will not receive it. It is too late to file a 2019 return to claim a refund. If you expect to have a balance due, then you should file the return to stop the penalties and interest from accruing.
However, you will not be able to use TurboTax to file a 2019 return because that version is no longer available for purchase through TurboTax. You can get the tax forms directly from the IRS website, or you may find another source for 2019 tax software.
Here is a link to find the forms from the IRS: Prior year forms and instructions