Welcome to the blackout period between the shutdown of the 2018 program and the launch of the 2019 program ... 

The ONLINE  system has permanently closed and is presently in transition from 2018 to 2019 versions.  

While the millions of returns are being archived the PDF download for tax year 2018 will only include the forms and schedules needed to file your tax return.  The worksheets and other pages are not included in the PDF until the 2019 online editions become available sometime in December 2019.

To access the PDF, log into the website with the userID you used to create the account - https://myturbotax.intuit.com/

Scroll down to the bottom of the screen and on the section Your tax returns & documents click on Show.  Click on the Year and Click on Download/print return (PDF)

How do I get a copy of a return I filed using online TurboTax?

https://ttlc.intuit.com/questions/1900748

How do I get a copy of a return I prepared using desktop TurboTax?

https://ttlc.intuit.com/questions/1900639

Note:  Every year, before mid-October, print a copy of your current year tax return and save it as a tax file and PDF, too.  That way you will have it when you need it for school, a loan, next year’s tax return, etc. without going through a lot of aggravation (and expense)  to get it.

Save as tax file :

https://ttlc.intuit.com/questions/1899645-how-do-i-save-my-2018-turbotax-online-return-as-a-tax-data...

Save as PDF:

https://ttlc.intuit.com/questions/1912544-how-do-i-save-my-2018-turbotax-online-return-as-a-pdf