radio button
<div class="custom-control custom-radio">
<input type="radio" id="customRadio1" name="customRadio" class="form-check-input" checked>
<label class="form-check-label" for="customRadio1">Custom radio</label>
</div>
<div class="custom-control custom-radio">
<input type="radio" id="customRadio2" name="customRadio" class="form-check-input">
<label class="form-check-label" for="customRadio2">Custom radio</label>
</div>
<div class="custom-control custom-radio">
<input type="radio" id="customRadio3" name="customRadio2" class="form-check-input" checked disabled>
<label class="form-check-label" for="customRadio3">Custom radio</label>
</div>
<div class="custom-control custom-radio">
<input type="radio" id="customRadio4" name="customRadio2" class="form-check-input" disabled>
<label class="form-check-label" for="customRadio4">Custom radio</label>
</div>