I took the index in the words, converted the range to binary, included 3 zeros, calculated the sha256 digest, took the initial part of the hexadecimal to convert it to binary, added three zeros to your 8 digits in the binary and bought 00000010011 which interprets to 19 in decimal. https://scrapbookmarket.com/story18811087/the-ultimate-guide-to-bip39-seed-phrase-mnemonics-generator