How do I access my 2018 return of I filed with turbo tax?

If you used the online product to file your 2018 tax return, use this link to help you access it: https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/00/27010

If you used the CD/download product, the only copy of that return would be on your computer.  TurboTax would not have it. 

I used the free edition for my 2018 return and just need to get direct deposit information/banking information for my refund. How can I get that info?

As long as your direct deposit option has a routing number and a bank account number, you can use it for your refund. Please click the TurboTax Help links, listed below, to learn more. 

Which number on my check is the routing number?

https://ttlc.intuit.com/community/refunds/help/which-number-on-my-check-is-the-routing-number/00/26183

Where do I enter my bank's routing or account number?

https://ttlc.intuit.com/community/entering-importing/help/where-do-i-enter-my-bank-s-routing-or-account-number/00/26300