JSFiddle - React, Tailwind, and code Playground

HTML

<div class="row">
  <div class="form-group col">
    <input type="checkbox" name="prd_presell" id="product_presell" 
      onclick="presellTXT()" value="TRUE">
    <label for="presell_product">Presell Product</label>
  </div>
</div>
<div class="row" id="show_presell_text">
  <div class="col-lg-12">
    <div class="form-group">
      <label>Product Presell Text:</label>
      <input name="prd_presell_text" id="presell_product_text" class="form-control">
    </div>
  </div>
</div>

JavaScript

function presellTXT() {
  var presell_checkbox = document.getElementById("product_presell");
  var presell_text     = document.getElementById("show_presell_text");
  if (presell_checkbox.checked == true) {
    presell_text.style.display = "block";
  } else {
    presell_text.style.display = "none";
  }
}