Example
$form = new Form('plugins-material-form-1', 'horizontal', 'novalidate', 'material');
$form->addPlugin('materialize', '#plugins-material-form-1');
$form->groupElements('user-name', 'user-email');
$form->setCols(0, 6);
$form->addIcon('user-name', '<i class="bi bi-person-fill" style="font-size:1.75rem;" aria-hidden="true"></i>', 'before');
$form->addInput('text', 'user-name', '', 'Name', 'required');
$form->addIcon('user-email', '<i class="bi bi-envelope" style="font-size:1.75rem;" aria-hidden="true"></i>', 'before');
$form->addInput('text', 'user-email', '', 'Email');
<div class="row form-group">
<div class="input-field col m6 s12">
<i class="bi bi-person-fill phpfb-addon-before prefix icon-before" style="font-size:1.75rem;" aria-hidden="true"></i>
<input id="user-name-material" name="user-name-material" type="text" value="" required class="form-control fv-group has-icon-before">
<label for="user-name-material">
Name <sup class="text-danger">* </sup>
</label>
</div>
<div class="input-field col m6 s12">
<i class="bi bi-envelope phpfb-addon-before prefix icon-before" style="font-size:1.75rem;" aria-hidden="true"></i>
<input id="user-email-material" name="user-email-material" type="text" value="" class="form-control fv-group has-icon-before">
<label for="user-email-material">
Email
</label>
</div>
</div>