if it already comes with turbo....is it just str8up turbo or there is stages to it?

Stages are pre-determined setups, Subaru has not such thing. In fact stages are the most rediculous idea when it comes to upgrades. It is more than likey factory.

If you would like to upgrade, head to NASIOC and do some research, mix and match, not one company is fgoing to make the exact thing you are looking for.

Yes, it is stock. l will just assume u bought it straight from a dealer & have not changed anything.

Stages r more for aftermarket upgrades. It provides a more clearcut path to different power levels & is generally a bit easier to describe ur car mods to someone else by saying ''My car is stage 2'' than rambling off an extensive list of modifications. Different tuning companies also define their stages slightly differently.

Generally, stages go a bit like this.
Stage 1: ECU tuning
Stage 2: ECU tuning + turboback exhaust
Stage 3: Stg 2 + upgraded turbo (with supporting mods)
Stage 4: Stg 3 + reinforced internals + upgraded transmission

As stated above, it varies a bit depending on tuning companies, but these r the modifications that add the most power on a WRX. You can look up companies such as Vishnu, Cobb, etc. to see how they define their stages. The average person will never really go above Stage 3, because at that point it becomes a lot pricier & harder to extract hp from ur engine, & u also greatly start sacrificing reliability..

Reading from what they've already said, l think it is mostly covered. Technically, it is a 'stage 0' if it is still mostly unmodified.
The stock WRX Turbo will put out about 11.5-12 lbs, which is a pretty good amount of boost, and it still will spool pretty quickly.