hi guys anyone have any idea what the standard noise level of a song is

Well, standardized where? The European Broadcasting Union (EBU) has created waves of measuring loudness so that an evenness can be implemented by radio stations without the most compressed track appearing the loudest.
 
https://tech.ebu.ch/loudness
 
A person named Bob Katz has suggested standardizing on -20 dB for movies and classical music, -14 for Jazz and Rock, and -12 for pop.
 http://en.wikipedia.org/wiki/K-system
 
He does take away the - sign when talking about these.
 
I use -14 most of the time because it sounds good to me.
 
When I watch netflix, I often monitor EBU and I can say that movies vary considerably in their volume. They are often louder than -20 measured using EBU 128, but the walking dead comes in considerably below (nearly -25). I think that helps get the surprisingly loud noises.

And when you're talking about the loudness level, it's RMS level. You'll get nowhere watching the peaks.
You can simply check the RMS and peak levels of any song you like yourself by importing them to SONAR or any audio editor.
You use the word "noise", but I assume you are not talking about the noise level/dynamic performance of the gear (/noise reduction), but the level of the actual signal.
 
The limiting level many use (for loud mixes) is around  - 0.03 dB, and it shouldn't be louder than that, if you think about, say, converting it to an MP3. And as mentioned, peaks don't make a mix  loud.

Sorry if I mislead anyone I'm mixing a song & I want to know what is the level it should be when converting to mp3

It's not a good idea to normalize everything to 0 when converting to MP3. The encoding process can increase the level above 0 and cause distortion. The pricey-but-excellent Sonnox encoder compensates automatically, but otherwise you'll need to do trial-and-error. I'd recommend starting with peaks hitting no higher than -1.5 dB, converting, and seeing where the peaks end up.

Anderton
It's not a good idea to normalize everything to 0 when converting to MP3. The encoding process can increase the level above 0 and cause distortion. The pricey-but-excellent Sonnox encoder compensates automatically, but otherwise you'll need to do trial-and-error. I'd recommend starting with peaks hitting no higher than -1.5 dB, converting, and seeing where the peaks end up.

Wow, Anderton! I was using -.3 or -.4 but never -1.5. That's a lot really! I've never noticed a problem with my mixes. I don't normally mix too hot anyway, so, it might be hard to catch an imperfection. That's a ton of headroom to leave though, imho.

And as gswitz and Kalle are saying, Average RMS level is what you need to look at, not peaks. A song could have the snare drum peaking at 0 and be only -22db Average RMS so will sound quiet. 
 
This is why mastering is another level of expertise. 

gswitz

Anderton
It's not a good idea to normalize everything to 0 when converting to MP3. The encoding process can increase the level above 0 and cause distortion. The pricey-but-excellent Sonnox encoder compensates automatically, but otherwise you'll need to do trial-and-error. I'd recommend starting with peaks hitting no higher than -1.5 dB, converting, and seeing where the peaks end up.

Wow, Anderton! I was using -.3 or -.4 but never -1.5. That's a lot really! I've never noticed a problem with my mixes. I don't normally mix too hot anyway, so, it might be hard to catch an imperfection. That's a ton of headroom to leave though, imho.

The Sonnox plug indicates how much it had to reduce level to avoid clipping. I often see -1.2 dB. Bear in mind, though, that the MP3 still reaches 0 or very close to it.
 
FYI the same thing can happen with Acidized loops. A loop that doesn't distort at one tempo may distort when stretched as the crossfading/mixing can create peaks not in the original.

Craig is an expert on this.
 
I mix with peaks between -5 and -3 if I am going to send the mix to a mastering engineer.  I want him/her to have some headroom.  The mastered product I get back is usually around -0.1.
 
What Katz says is great, but if you mix at -14, people will think something's wrong because your music is so quiet. A healthy debate about loudness is good, but if consumers have to get up and adjust the volume when your music comes on, they won't be happy.

Wow guys I feel a bit blown away... U guys are fantastic.... Might post a question about the universe ses what happens lol 😀😀