I took the index on the words, converted the amount to binary, additional a few zeros, calculated the sha256 digest, took the main part of the hexadecimal to convert it to binary, included 3 zeros for the 8 digits of the binary and bought 00000010011 which translates to 19 in https://bookmark-nation.com/story19311725/examine-this-report-on-bip39-mnemonic-phrase-tool