I took the index in the words, converted the selection to binary, added three zeros, calculated the sha256 digest, took the very first part of the hexadecimal to convert it to binary, added 3 zeros into the eight digits of your binary and got 00000010011 which translates to 19 in https://bookmarkilo.com/story19486531/considerations-to-know-about-bip39-word-list-pdf