Bip39 Tool. Entropy values has to be sourced from a robust source of randomness. This means flipping a fair coin, rolling a good dice, noise measurements etcetera. Don't use phrases from publications, lyrics from songs, your birthday or steet tackle, keyboard mashing, or anything at all you think is random, https://lombok-directory.com/listings13050196/bip39-seed-generator-https-linktr-ee-bip39-an-unbiased-view-of-bip39-checksum