I just picked up my 1st G35 a week ago and have noticed that when im parked and start the car the RPM is at 2k and once i put it on R to back out of my driveway it drops too 1k.

Is this normal?

I did a quick Google search and read that someone had a similar issue and people were saying it has to do with his exhaust,

So i think it might be smart to mention the car had been in a small accident from the back right, and i believe one of the exhausts were replaced along with the back bumper

How long do you let the car warm up for? That is typical for a cold start.

^^ +1

If it goes to 2k when it's fully warmed up, then you've got a concern, but if it only does it when cold, it's completely normal.

Its cold in LA right now and when i start the car for the 1st time in the morning it sits at 2k and after a while goes down and idles at 1k.

Totally normal.

If you wait a bit longer still, it will probably idle down to the 700-800 range.