HTML

<label for="password">Password <span class="star">*</span></label>
<input required aria-required="true" aria-describedby="password-description" type="password" name="password" id="password">
<br>
<span id="password-description">Use 6-20 characters, at least 1 uppercase letter and 1 number.</span>

Output

Password *
Use 6-20 characters, at least 1 uppercase letter and 1 number.