reactcrm/app/views/settings/_form.php

<?php

use yii\helpers\Html;
use yii\bootstrap4\ActiveForm;

/* @var $this yii\web\View */
/* @var $model app\models\Settings */
/* @var $form yii\widgets\ActiveForm */

?>

<div class="settings-form">

    <?php $form = ActiveForm::begin(); ?>

    <?php
    $dayItems = [];
    $timeItems = [];
    for ($i = 1; $i <= 31; $i++){
        $dayItems[$i] = $i;
        if($i >= 8 && $i <= 18 ){
            $timeItems[$i] = "${i}:00";
        }
    }
    ?>

    <div class="row">
        <div class="col-4 col-xs-12"><?= $form->field($model, 'invoce')->dropDownList($dayItems, ['prompt' => 'select']); ?></div>
        <div class="col-4 col-xs-12"><?= $form->field($model, 'act')->dropDownList($dayItems, ['prompt' => 'select']); ?></div>
        <div class="col-4 col-xs-12"><?= $form->field($model, 'time')->dropDownList($timeItems, ['prompt' => 'select']); ?></div>
    </div>

    <div class="form-group">
        <?= Html::submitButton('Save', ['class' => 'btn btn-success']) ?>
    </div>

    <?php ActiveForm::end(); ?>

</div>