The questions asks about IRA contributions prior to 2018. Is that asking for all contributions and where would I get that information?
Yes, the question is asking about all your prior contributions. The information would be in your IRA account statements and Forms 5498 that you have received over the years.
You have clicked a link to a site outside of the TurboTax Community. By clicking "Continue", you will leave the Community and be taken to that site instead.