There are 12 natural scales :they all sound like this -
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All the A chords can be worked out from A natural scale

All the A# chords can be worked out from A# natural scale

All the B chords can be worked out from B natural scale............etc

A natural scale is : A..B..C#..D..E..F#..G#..A..

A major chord, contains, the First, the Third, and the Fifth notes of A natural scale.................A......C#......E

A minor chord, contains, the First, the Flatenned Third, and the Fifth notes of A natural scale.......A......C........E

A7 chord, contains, the First,the Third, the Fifth and the Flat Seventh notes of A natural scale.......A.......C#.....E.........G


B natural scale is : B..C#..D#..E..F#..G#..A#..B

B major chord, contains, the First, the Third and the Fifth note of B natural scale...................B........D#.....F#

And so on