in the audio mixer window under the last fader section (master fader) to your right, you find a little buton underneath the fader saying "bounce" if you click on it a pop-up window appears where you can bounce down (create either an split stereo or interleaved stereo file of your tracks, you probably want interleaved unless you want to work further in say pro tools... )

nevertheless, read the manual again!!

a.

Thank you.