1. If you are logged into the account you prepared your 2016 return in and are seeing that, it means you chose the File by Mail option instead of e-File. So you will need to print and mail your return if you choose to file a paper return or you are prompted to mail the return.
You can go here https://shop.turbotax.intuit.com/efile/efile_status_lookup.jsp to check to see if you have already e-filed the return.
This link will give you the instructions on how to print and mail if you are using the TurboTax Online version of the software https://ttlc.intuit.com/questions/1944348
2. If you need to switch to e-file instead, you can find the steps to do that below. Click on "Change to e-file your return in TurboTax Online versions" below and it will show you the instructions for how to do that.