Key of "..."

[ModestMouse2003]

Ok, i figured out why songs need to have a key, basically for improv and lead right??

well how exactly can i find scales in a certain scale?

i have a sheet that shows the minor scale, the major scale and others

but not necessarily the key of "D" for example

does this make sense?


EDIT: NEVERMIND, i figured it out doing a search, im a lazy ass.