Let's look at a one octave G major scale. Starting on the root note on the G major scale.
I like to start this scale with the 2nd finger holding down the root note as it will be the same finger for both the chord and the scale.
Remember to play the chord before and after playing the scale you want them to be one thing in your head so when playing a chord you know all the scale notes you can play and when improvising you know the chord tones within the scale you are using.
In this scale we have a # (sharp). A sharp is when you raise a note by a semitone. Easiest seen on the piano, the white keys are all the natural notes. The black keys are the # (sharps) and the b (flats). C major and A natural minor and their modes are the keys that have all natural notes. The rest will have some sharps or flats in them to keep the shape (intervals) of the scale correct.
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