Bip39 format example https://www.demilked.com/author/gobnettlmz/ Checksum generation: A checksum is generated from this entropy using SHA-256 hashing, which will help validate the mnemonic's integrity later. Because of the cryptographic style and design of BIP-39, a weak passphrase doesn't reduce the safety of the other wallets or help expose the seed words. https://pageoftoday.com/story5457531/bip39-eth-new-step-by-step-map-for-bip39-github-https-dzen-ru-bip39-phrase-com