It's not important to know all the details of BIP39 as a way to use copyright - however, you will surely reap the benefits of understanding a bit over it. This text explains BIP39, the standard that defines how seed phrases are made, and summarizes how BIP32 and BIP44 standards https://ledbookmark.com/story4550101/bip39-seed-phrase-mnemonics-generator-an-overview