Chords and Chord Progression

While messing around in GarageBand, I started using the keyboard piano using the MacBook keys (cmd + k). I was just making random sounds and did not really know what I was doing. I decided to learn more about how to make chords, which are a series of notes played simultaneously. They would sound much better than random notes playing. There are a variety of possible chords, it is a topic that has a low skill floor but a very high skill ceiling. It can be very complex but I learned it in a more simple terms. I watched lots of youtube videos and online references to learn about chords and how they work. In the end, one video did help me by Busy Beats Works. They explained simple chords in simple terms. You can start a chord on basically any note. You then can count up 4 notes to the second note, and 7 notes up from the second note. In the end you should end up with a 0-4-11 chord pattern