A Form 1098 is the form you received and then entered the tax data on the tax return. The actual form is not included in the tax return only the information from the form is entered on a worksheet.
To view or print the TurboTax worksheets before filing a tax return you would need to pay the TurboTax account fees.
To pay the TurboTax online account fees by credit card, without completing the 2020 return at this time, click on Tax Tools on the left side of the online program screen. Then click on Print Center. Then click on Print, save or preview this year's return. On the next page, to pay by credit card, click Pay Now. The next screen will show a review of your Fees, click on Continue. Complete the next screen to pay by credit card and click Continue.
Online TurboTax does not include forms mode. Forms mode is a feature of the CD/download. You could go to the bank's site yourself to see your own 1098 and compare it to the data that you dowloaded if you have concerns about its accuracy. You are not required to download a 1098---you can always just key it in yourself if you have a copy from the lender.
Thanks @DoninGA ! Duh oops! Where can I view whether my mortgage interest was capped (my mortgages exceed $750k combined so want to make sure)
@jasonthomasy The mortgage debt caps would be on the Home Mortgage Interest Worksheet. This Mortgage Interest information flows to Schedule A Line 8.
Schedule A and the Worksheet are not included in the Preview My 1040 for the online tax returns. You would still need to pay the TurboTax account fees to view/print Schedule A and the Worksheet before filing.