Please read the moderator's comments thoroughly. I'd also recommend writing down the idea so you can see it. Using this formula for constructing a major scale, the scale will be the same for all major keys. For example, C major scale = C D E F G A B C (1,1,1/2,1,1,1,1/2) (interval distance between notes)
Chord building:
C E G = C maj chord (triad)
D F A = D min chord (triad) etc.
Do this for all keys. Then do it again for 4 note chords or 7 type chords.
C major scale C D E F G A B
C E G B = Cmaj7
D F A C = Dm7
E G B D = Em7 and so on.

In all major scales this chord formula arises.
I, ii, iii, IV, V, vi, vii
Capital roman numerals are always major within the key
and small roman numerals are minor. vii is a half diminished. Naming four note chords can be complicated if you don't know how chords are stacked or built. You will ultimately find that chords repeat themselves in other keys.
You'll also notice that keys themselves work in cycles.
That's when life gets really fun. Hope this helps a little.