You don’t need decks to use Ableton.
Ableton is a sequencer that lets you make music… but also lets you dj as well, in 2 ways.
1st way – you can create a dj set off-line (not LIVE), in arrangement view.
2nd way – you can do a dJ set LIVE, in real time, using the session view and a midi controller.
Ableton - Live 8
If you want to use decks and records... then Ableton is not for you.
I thought it was to make music, but do you need turntables? I don't get it. It seems really complicated.