HTMLSelectElement.options

<label for="test">Label</label>
<select id="test">
  <option value="1">Option 1</option>
  <option value="2">Option 2</option>
</select>

window.addEventListener("DOMContentLoaded", function() {
  const select = document.getElementById("test");
  for(var i = 0; i < select.options.length; i++) {
    console.log(select.options[i].label); // "Option 1" and "Option 2"
  }
});