I took the index from the words, transformed the number to binary, additional three zeros, calculated the sha256 digest, took the initial part of the hexadecimal to convert it to binary, included three zeros towards the 8 digits in the binary and acquired 00000010011 which translates to 19 in decimal. https://webnowmedia.com/story4297970/bip39-seed-phrase-mnemonics-generator-an-overview