<div id="1">
 <button>button</button>
</div>

<div id="2">
 <button>button</button>
</div>

<div id="3">
 <button>button</button>
</div>

<div id="output"></div>

function getParentId(el) {
  const id = el.parentElement.id;
  document.getElementById('output').textContent = `Id родителя - ${id}`;
}

let btns = document.querySelectorAll('button');
btns.forEach((btn) => {
  btn.addEventListener('click', () => {
    getParentId(btn);
  });
});