need help: Pianoteq under ableton9 on OSX

My first post here, so a big Hello from my side to everyone !

The situation:
i want to play Pianoteq from ableton Live-lite 9 to be able to add some Software Reverb and other FX.
The Problem:
These days, I have NO clue anylonger about DAW, VSTs, and anyway not MacOS in that regards ( i´m on OSX 10.11.2 ).

The Mac is a totally new setup miniMac, so there are quasi no files on it.
I can´t find any .vst file or Folder on it.

so what do i have to do to get my Pianoteq running within ableton ?
I fear i really need a step by step help.
my guess, from reading in another thread here: First: reinstall pianoteq ?
but: do i need to have allready a VST Folder bevore i proceed ? here my series of questions starts............

help much aprecciated