You received your refund for your 2018 return? What are you trying to do now? You do not have to pay to print your 2018 return.
PRINT RETURN You need to print a copy of your return? Sign in to your account using exactly the same account and user ID that you used to prepare your return.
On the bottom of the screen find Your tax returns & documents and click on Show. Click on the Year and Click on Download/print return (PDF)
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.
https://ttlc.intuit.com/questions/1912544-how-do-i-save-my-2018-turbotax-online-return-as-a-pdf
Or are you asking about your 2017 return you filed in 2018?
If you actually meant your 2017 return that you filed in 2018:
https://ttlc.intuit.com/questions/3404575-how-do-i-access-my-prior-year-2017-return
You can get a free transcript from the IRS:
I do not have my 2918 return, I need information from it to file my 2019 return.
Follow these steps to get a copy of your prior-year tax return.
Sign in to TurboTax making sure you're using the same TurboTax account (with the same username) as in prior years.
Select Documents from the navigation when it appears.
Use the drop-down menu at the top of the screen to choose the tax year you want and then select Download PDF.
This link How do I access a prior year return? has additional information that you may find useful