Bip39 Vs Slip39. At the start you ought to retailer it SEPARATELY from your seed. Owning your seed along with your passphrase in the same location defeats the goal of having a passphrase to start with. BIP39 specifies a list of 2048 words from which the mnemonic phrase is picked. https://socialaffluent.com/story4673485/ian-coleman-bip39-https-linktr-ee-bip39-5-simple-statements-about-bip39-mnemonic-explained