govuk-frontend/dist/govuk/components/radios/template-prechecked-using-value.html

GOV.UK Frontend contains the code you need to start building a user interface for government platforms and services.

<div class="govuk-form-group">
  <div class="govuk-radios" data-module="govuk-radios">
    <div class="govuk-radios__item">
      <input class="govuk-radios__input" id="example-default" name="example-default" type="radio" value="yes">
      <label class="govuk-label govuk-radios__label" for="example-default">
        Yes
      </label>
    </div>
    <div class="govuk-radios__item">
      <input class="govuk-radios__input" id="example-default-2" name="example-default" type="radio" value="no" checked>
      <label class="govuk-label govuk-radios__label" for="example-default-2">
        No
      </label>
    </div>
  </div>
</div>