I took the index of the words, transformed the number to binary, added a few zeros, calculated the sha256 digest, took the 1st Portion of the hexadecimal to convert it to binary, extra 3 zeros to your eight digits of the binary and got 00000010011 which translates to 19 in https://ledbookmark.com/story4486790/bip39-seed-phrase-mnemonics-generator-an-overview