Got a Problem
 

My 01 2500 6.0 is make a whining nose when i start it up and goes away after i put it in gear whats going on ??

Does it have California Emissions equipment, AKA AIR pump?

Also, what "kind" of whine is it. From where do you think it's coming from?

Well I just moved from Ca to Ky so it does have Ca emissions .. But like when I start it on its kinda loud in park and increase rpm it getting louder .. I put it in gear it seems to decrease in sound but I still hear it idk I got told it could be my power steering or Tanny

It's hard to diagnose with out seeing and hearing it in person.
It could be almost anything from something wearing in the bottom end of your engine to an issue in your tranni.
What ever it is, it's related to the drive train. Cause as you say it seems to somewhat subsides when your drivetrain louds up in drive

Well I replaced my tranny filter and the noise sounds better but there was a lot of metal in the pan lol so we will see how it goes thanks for the help

oohh ... yep that could very well the the cause. Definitely sounds like power steering or transmission pump.

Sounds like you will be shopping for a Tranni in the near future or a transmission shop now before it gets REALLY expensive