Did you file your return from the Online version? Have you paid for the Online version or it wants to charge you?
If you already started in the Online version you can move your return to the Desktop program even without paying for Online.
First download the .tax2018 file from the Online version,
<a rel="nofollow" target="_blank" href="
https://ttlc.intuit.com/questions/1899645-how-do-i-save-my-2018-turbotax-online-return-as-a-tax-data...Then see, How to Switch to Desktop,
<a rel="nofollow" target="_blank" href="
https://ttlc.intuit.com/questions/1901476-how-do-i-switch-from-turbotax-online-to-the-turbotax-softw...After you get the program installed the first thing to do before you open your tax return is to update the program and install any state programs you had. Then open your file. So you first might need to start a fake return to be able to download the state program (go to FILE - NEW).
Go to Applications and open the TurboTax 2018 program.