Bip39. The wallet handles the large lifting of changing the mnemonic words via a strategy of complex hashing, salting, and checksum functions right into a binary "seed," that's then used to deliver the all-critical private and public encryption keys. Remember the fact that using a passphrase also has some tradeoffs, https://ontopicdirectory.com/listings13109206/bip39-words-https-linktr-ee-bip39-bip39-words-an-overview