You can download the 2018 forms from the IRS web site below, but TurboTax no longer supports software for the 2018 tax year.
https://www.irs.gov/prior-year-forms-and-instructions?find=1040&items_per_page=200
You might also want to seek guidance from a local tax professional.
https://taxexperts.naea.org/expertdirectory
