It's not easy to understand and digest the stuff under https://learnmeabitcoin.com/technical/cryptography/elliptic-curve/ and maybe it's also beneficial to read about elliptic curve "magic" in other sources like Mastering Bitcoin or even completely different ones before the stones fall into their places.

Don't expect to understand it within minutes, hours or days unless you're a "Wunderkind" or math prodigy.