Dev,
Stare at a keyboard in a music store. It does not have to be expensive. Most any keyboard will do.
Put your left hand pinky on the C below middle C and play these notes up in a row, playing all white keys and skipping none. When you run out of fingers on your left hand, pick up with your right thumb.
C D E F G A B C.
Also known as Root (1), 2nd, 3rd, 4th, 5th, 6th, 7th, Root
Now with your left hand pinky on that lower C, add in the E with your middle finger (that is the third, C is the 1). Also add your thumb to the G, the 5th.
That is the C major chord triad.
Play it several times. Listen to the beauty. Play this chord with your left hand. Later you will learn to add melody notes with your right hand, but that is for another day.
Now take that SAME SHAPE and move the whole thing up by one key.
That is D minor. The second chord. (Minor second.) D F A
Move up one more key.
That is E minor. The minor third. (In chord theory.) E G B
Move up one more.
That is F. The fourth. F A C
Move again. That is G. The fifth. G B D
Move again. A minor. The minor 6th. A C E
Move again, playing B, D, F.
That is B diminished. (The triad.)
Move one more.
You are back at C. C E G.
Stare at your hands while you play these chords.
All of music is in there, it's just key changes and accidentals from there...but most songwriters use little more than that.
Try it.
You will fall in love.
I promise.
