Columbia Essays Overthinking

Hi there! With decisions coming out I am overthinking everything.
In the why Columbia supplemental, I talked about how I like the Core because it is rigorous, flexible, and perfect for my diversified interests. I’m not sure about the “flexible” anymore, it was my understanding at the time since we can choose what classes we can take to fulfill each category (Frontiers of Science, Music Humanities, etc.), but is this right? It seems like a flexible system to me since I grew up where I didn’t get to choose my classes until I moved here. Thank you!

Contemporary Civilization, Literature Humanities, Music Humanities, Art Humanities, Frontiers of Science, University Writing are distinct courses that all Columbia College students take - not categories from which there are courses to choose.