Where can we use codes

Can we use the codes in iw4 console when we are in a public game and arent host?
and Is there a code for unlimited Killstreak or Carepackage?

Thanks

O and how to make it so when we type in the super jump code it stays the whole game instead of having to type it everytime i die?

You can use client-sided codes, Like Cg_Fov 80
But that's basicly it
And for the unlimited killstreak's you have to make a mod to make it work... As far as I know xD