Minor scales have three versions because the seventh scale degree, called the leading tone, is flatted.
The three minor scales: natural, harmonic, melodic. When you see harmonic; think chords. You need to spell the scale correctly. Make sure the roots are in alphabetical order: C, D, Eb, F, G, Ab, Bb, C. This is the natural minor - meaning that it has the same notes as the relative major: Eb Major.
The issue is that the V7, or DOMINANT chord of the key of Eb Major is Bb7. Playing the Bb7 establishes the key of Eb. If you are in C Minor, the V chord is minor (in the natural minor) and the DOMINANT is on the seventh scale degree and will drive the ear to Eb, not C. To make a DOMINANT for the key of Cm, you raise the 7th scale degree, Bb in the natural minor. Doing this eliminates the old dominant from the relative major, and more importantly creates the tritone in the right place for the Dominant to establish the Minor i, C Minor.
Once you raise the 7th scale degree, get the Minor key chords as you would in the Major: start on each scale degree and go in 3rds (every other note). Then look at what chord it spells. Here are the triads.
Harmonic Minor: C, D, Eb, F, G, Ab, B, C
Cm(C, Eb, G) Ddim(D, F, Ab) Eb+(Eb, G, B) Fm(F,Ab, C) G7(G, B, D, F) Ab(Ab, C, Eb) Bdim(B, D, F)
It's really cool to keep adding 3rds for the 7th, 9th, etc and see what you get.