i just threw a new nicholson file in the oven to get to the right hardness and there is some white smoke coming off of it, is this stuff gonna kill me?

Right hardness for what?
Anything that goes in the house oven or the toaster oven inside gets thoroughly degreased.

for a knife lol, i dont like how brittle they are new

Ah. I think what you are trying to do is anneal the file, to soften it, yes?

If so, you won't get any joy from a kitchen oven. To anneal, you first need to heat the file to it's critical temperature (if you get it an even 'orange' hot, you'll not be too far off the mark) You'll need to do this in an actual fire. Either a forge or a charcoal BBQ will get it there. You then need to let it cool, very very slowly. Your best bet is to throw it onto a raging hot BBQ, cover it in charcoal & let it sit there burning overnight.
That 'should' get it soft enough to work with.

What Rob said  :D
Just throwing a file in the oven will draw back the temper enough so you can work it with tools, but it'll be REAL slow going and REAL tough on tools.  Your best bet is a full (or nearly so) anneal.

Did you get that miniforge up and running?  If so, throw the file in there until it gets to critical, then quickly bury it in a bucket of hardwood ashes (with a few hot coals thrown in if possible).  If no ashes, just bury it in sand (again with the hot coals)... that won't give you a full anneal, but it'll be close enough.

no, i was tempering it lol. i was going thru the annealing it and then hardening and tempering it to make sure i wa doing it right and wouldnt kill a blade that i have a couple hours into.

Well why didn't you say so man!  :D

As I said, anything that goes in an oven in the house gets degreased, and usually ground to bare metal before that.

sorry lol, i was pretty sleepy last night and just figured i would post this to make sure that funny white smoke coming from the hunk of steel in the oven wasnt gonna kill me especially right before season  

That's why I got my little toaster oven from the Goodwill store for $5.  It heats up to about 450 and I can keep it out in my shop and I don't get yelled at by herself.

The smoke ain't gonna kill ya but your folks probably will . . .That's sometimes pretty tough to get out of the oven & kitchen!!!    

Larry