Can I use turbo tax online for my 2017 tax return and pay after I file my 2017 tax return

No, No, and No. 

1) Prior year returns can't be done on-line.

2) Prior years can't be done via app or e-filed; pay for/download software/forms, then print/sign/mail.

3) You can pay TurboTax to download software, or get forms/instructions free at IRS.gov.

Online preparation and e-filing for 2017 is permanently closed.

To file a return for a prior tax year

If you need to prepare a return for 2015, 2016, or 2017 you can purchase and download desktop software to do it, then print, sign,  and mail the return(s)

https://turbotax.intuit.com/personal-taxes/past-years-products/

Remember to prepare your state return as well—if you live in a state that has a state income tax.

When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s.  Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS/state received the return.

Note:  The desktop software you need to prepare the prior year return must be installed/downloaded to a full PC or Mac.  It cannot be used on a mobile device.