Bip39 Seed Phrase. You'll then do a simple Restoration by using a command like the a person under. (This command makes use of a sample wallet file bunlded with BTCRecover) Any one else who discovers the phrase can steal the bitcoins. It need to be held secret, one example is https://dmozbookmark.com/story18947132/bip39-https-linktr-ee-bip39-getting-my-bip39-passphrase-to-work