It is probably gone. TurboTax and the IRS save returns for seven years, and then they are purged. You can check, but do not expect much.
You have to access your own account and/or print it for yourself using exactly the same account and user ID that you used when you prepared the return.
Start a 2023 return online and enter some personal information so that the menu on the left opens up and lets you access your past year returns.
Many people have multiple TT accounts and forget how to access them. Log out of the account you are in now.
https://ttlc.intuit.com/questions/1901535-forgot-your-turbotax-online-user-id-or-password
https://ttlc.intuit.com/questions/1901486-how-many-turbotax-accounts-do-i-have
Or did you use the desktop version of TurboTax? If so, the files are on your own hard drive or any backup device you used like a flash drive.
https://ttlc.intuit.com/questions/1901659-find-your-tax-data-file-in-mac
You can get a free transcript from the IRS or for a fee of $30, an actual copy of your tax return.
https://www.irs.gov/individuals/get-transcript
https://www.irs.gov/pub/irs-pdf/f4506.pdf
SAVE YOUR TAX RETURN !
EVERY year before mid-October you should save a copy of your tax return as a pdf and print a copy of it for your records. That way you will not be searching online frantically when you need it for a lender, FAFSA forms, your next tax return, etc.
https://ttlc.intuit.com/questions/1900937-why-should-i-save-a-pdf-copy-of-my-return
NOTE: TurboTax and the IRS save returns for seven years. Returns older than seven years are purged.
if it's gone so would the IRS transcripts. Fir a fee you can get a copy of your 2016 W-2 from the Social security Adm. Certain other sources if you remember them like brokerages/mutual funds may be able to provide the 2016 tax forms. you would have to contact them