Bip39 Tool. The passphrase is not picked within the predefined list of 2048 words – it might be any word or phrase you choose. BIP39 can be a design implementation that lays out how copyright wallets produce the list of words (or "mnemonic codes") which make up a mnemonic sentence, https://bookmarkity.com/story18832469/bip39-generator-https-linktr-ee-bip39-the-best-side-of-bip39-mnemonic