I took the index from the words, transformed the range to binary, additional 3 zeros, calculated the sha256 digest, took the 1st Element of the hexadecimal to convert it to binary, included a few zeros towards the eight digits of your binary and acquired 00000010011 which translates to 19 in https://bookmarkcitizen.com/story19038583/bip39-phrase-generator-can-be-fun-for-anyone