CODE EXAMPLE FOR PHP

multiple select options laravel

<select class="form-multi-select" id="ms1" multiple data-coreui-search="true">
  <option value="0">Angular</option>
  <option value="1">Bootstrap</option>
  <option value="2">React.js</option>
  <option value="3">Vue.js</option>
  <optgroup label="backend">
    <option value="4">Django</option>
    <option value="5">Laravel</option>
    <option value="6">Node.js</option>
  </optgroup>
</select>