I am trying to set this input control using $input_group.find('input'); but it is not getting set. Is this the correct way to use find and then set the value of the input control or is there anyway to do this?
            var $container = $('#gridrow-field-container');
            var template = $('#gridrow-template-input-group').get(0);

            $(item.MeetingPollingPartsValues).each((indexPartsValues, PartsValues) => {
                var $input_group = $(template.content.cloneNode(true));
                var inputControl = $input_group.find('input');
                inputControl.val(PartsValues.QuestionValue);

                console.log(inputControl);

                console.log($input_group);
                $container.append($input_group);
                $('input_group').val(PartsValues.QuestionValue);
            });


 <template id="gridrow-template-input-group">
         <div class='row mb-3' id='newrowItem_1'>
            <div class="input-group">
               <input type='text' id='fieldrowItem_1' name='name[]' class='form-control fieldrowItem mb-3' placeholder="Row 1" data-value="0" >
               <span  id='spanrowItem_1' class="input-group-addon" style="cursor:pointer;"  onclick="RemoveRow(this)"  >
                  <i class="fa fa-remove" style="color:#CDCDCD"></i>
              </span>
         </div>
         </div>
 </template>


Set value of input control from input_group
I added Bootstrap 5 dependencies and fixed the template.
You can clone the contents of the template with:
const $inputGroup = $template.contents().clone();



const $container = $('#gridrow-field-container');
const $template = $('#gridrow-template-input-group');

const RemoveRow = (span) => {
  $(span).closest('.row').remove();
}

const item = {
  MeetingPollingPartsValues: [
    { QuestionValue: 'One'   },
    { QuestionValue: 'Two'   },
    { QuestionValue: 'Three' }
  ]
};

$(item.MeetingPollingPartsValues).each((index, partValue) => {
  const $inputGroup = $template.contents().clone();
  const $inputControl = $inputGroup.find('input');
  $inputControl.val(partValue.QuestionValue);
  $inputControl.attr('placeholder', `Row ${index + 1}`);
  $inputControl.attr('data-value', partValue.QuestionValue);
  $container.append($inputGroup);
});
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-9ndCyUaIbzAi2FUVXJi0CjmCapSmO7SnpJef0486qhLnuZ2cdeRhO02iuK6FUUVM" crossorigin="anonymous">
<link href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.4.0/css/all.min.css" rel="stylesheet"/>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/js/bootstrap.bundle.min.js" integrity="sha384-geWF76RCwLtnZ8qwWowPQNguL3RmwHVBC9FhGdlKrxdiJJigb/j/68SIy3Te4Bkz" crossorigin="anonymous"></script>
<template id="gridrow-template-input-group">
  <div class="row">
    <div class="input-group mb-3">
      <input type="text" name="name[]" class="form-control"
          placeholder="Row x" data-value="0" >
      <div class="input-group-text" style="cursor:pointer;" onclick="RemoveRow(this)">
        <i class="fa fa-remove" style="color:#CDCDCD"></i>
      </div>
    </div>
  </div>
</template>
<div id="gridrow-field-container" class="container"></div>



