The triad is much more coherent if you listen and understand the context in which the chord appears. It’s usually part of a chordal sequence. In the video, you will see and listen to the following chordal sequence: ♭II - i64 - V - i
Below, you will see two sets of chordal sequences, the second sequence omitting the i64.
Study the following two sequences. You might be able to understand the chords better by playing them on a keyboard or by listening to them. The key is C minor.
Try this one too.