elements: [
{value: 'pizza', active: true, hidden: false, words: [value.split('')]},
{value: 'sushi', active: false, hidden: false},
{value: 'steak', active: false, hidden: false}
]
const elements = [
{ value: "pizza", active: true, hidden: false },
{ value: "sushi", active: false, hidden: false },
{ value: "steak", active: false, hidden: false }
];
elements.forEach(element => element.letters = [...element.value]);
console.log(elements[0]); // { value: "pizza", active: true, hidden: false, letters: ["p", "i", "z", "z", "a"] }