looooooooooooop.js

const entities = [ ... ]

function update () {
    setTimeout(() => update(), 1000 / 60);
    
    for (const entity of entities) {
        entity.update();
    }
}

function draw () {
    requestAnimationFrame(() => draw());
    
    for (const entity of entities) {
        entity.draw();
    }
}

function startGameLoop () {
    update();
    draw();
}