You receive two parameters: a list of words words and a word word. First, it finds the index of the word in the list. It then uses that index (which will be a number) and returns all words in words that are longer than the index number. Note that the word word will always exist in the array, so there is no need to check whether it exists or not.
function getWordsMoreThan(words, word) { let index = words.indexOf(word) let result = words.filter(x => x.length > index) return result }