After you file

So, I failed to finish my 2018 return by October because I was having difficulty obtaining some documents.  Aside from 2 minor documents, my return was ready to file as soon as I was able to.  Today, I logged back on but now I cannot access my 2018 return to complete.  The message board seems to allude to my being able to complete it now or even access all the work I've done.  How can I get all the work I did on TurboTax online?  How can I then file my 2018 return with the work I completed online?  Thank you.