I took the index in the words, transformed the quantity to binary, included three zeros, calculated the sha256 digest, took the initial Section of the hexadecimal to convert it to binary, added a few zeros for the 8 digits with the binary and obtained 00000010011 which interprets to 19 in https://ledbookmark.com/story4434917/getting-my-bip39-words-to-numbers-to-work