I took the index from the words, converted the selection to binary, extra three zeros, calculated the sha256 digest, took the main Section of the hexadecimal to transform it to binary, extra 3 zeros to your eight digits with the binary and received 00000010011 which translates to 19 in decimal. https://bookmarkfox.com/story5190470/5-simple-techniques-for-bip39-seed-phrase