You'll continue through the TurboTax interview all the way to the place where you select to "Transmit Return Now". Once you've done that, you should see a notice that your transmission was successful.
You'll also receive an email notifying you whether your return has been either "Accepted" or "Rejected" by the IRS. If your return has been accepted, you're finished. If your email says that your return has been "Rejected", you'll have instructions about what need to be "fixed" before you re-submit your return.
How do I e-file my personal individual tax return?