In music a major scale always has the same chromatic formula. As you go up the scale the notes you need to play (after you've played the first note you choose - or root note) are tone, tone, semi-tone, tone, tone, tone semi-tone.
Play that relative pattern starting on any note and you'll have played a major scale of whatever note it was you started from.
So, on a piano, if you start on C it's all the white notes