Get your taxes done using TurboTax

Sorry for the delay, had to run an errand.  Re online version vs Desktop CD/Download program to my computer, I'm not sure.  I know I did not use a CD or Download any program to my computer, so I assume it would be the online version.  Re what is stated under 2019 tab, it asked if I wanted to downlead a copy of my 2019 return.  I selected yes.  It asked why I wanted a copy of my 2019 tax return.  I wrote, "To see what actually got filed with the IRS in 2020 for tax year 2019. I was told by an IRS rep in December 2020 that they had nothing on file re my 2019 tax return."  Turbotax said okay, downloaded a filled-out Form 1040-X & a filled-out Form 1040 for my Federal and State taxes.  This information came downloaded in a 125-page pdf.  Amazingly, I do not know where Turbotax got the figures it plugged into all those boxes because I don't feel smart enough to even know how all those figures came about when I did not even have my 2019 W-2 information when I submitted my Federal and State returns on July 15, 2020?  Further, I do not remember submitting any 1040-X.  And how did Turbotax get my W-2 information to plug into the filled out Form 1040?  Is there a way to tell in Turbotax when these Forms 1040 & 1040-X were filled out and presented to the IRS?  A few days ago, I filled out my 2019 Federal and State tax returns online and planned to print and mail them next week.  Now, I'm not sure what to do as I just might make matters worse if I mail them.  I'm baffled. ðŸ¤•