How to display your array in opencart product?

Question

CMS

Good afternoon! You need to display the field in the opencart admin panel (in the product), with the ability to add an infinite number. such fields (that is, make an array). The question is how to do it in terms of php?
I render the fields like this:

<file path="catalog/controller/product/product.php">
        <operation error="log">
      <search>
        <![CDATA[
          $data['points'] = $product_info['points'];
        ]]>
      </search>
      <add position="after"><![CDATA[
          $data['features'] = html_entity_decode($product_info['features'], ENT_QUOTES, 'UTF-8');
          $data['specifications'] = html_entity_decode($product_info['specifications'], ENT_QUOTES, 'UTF-8');
          $data['documentations'] = html_entity_decode($product_info['documentations'], ENT_QUOTES, 'UTF-8');
          $data['href_product'] = $product_info['href_product'];
          $data['instructions'] = html_entity_decode($product_info['instructions'], ENT_QUOTES, 'UTF-8');
        ]]>
      </add>
    </operation>
</file>

<file path="catalog/model/catalog/product.php">
        <operation error="log">
      <search>
        <![CDATA[
          'name'             => $query->row['name'],
        ]]>
      </search>
      <add position="after"><![CDATA[
          'features'             => $query->row['features'],
          'specifications'             => $query->row['specifications'],
          'documentations'             => $query->row['documentations'],
          'href_product'             => $query->row['href_product'],
          'instructions'                 => $query->row['instructions'],
        ]]>
      </add>
    </operation>
  </file>
<file path="admin/model/catalog/product.php">
        <operation error="log">
      <search>
        <![CDATA[
          model = '" . $this->db->escape($data['model']) . "',
        ]]>
      </search>
      <add position="replace"><![CDATA[
          model = '" . $this->db->escape($data['model']) . "', specifications = '" . $this->db->escape($data['specifications']) . "', features = '" . $this->db->escape($data['features']) . "', documentations = '" . $this->db->escape($data['documentations']) . "', href_product = '" . $this->db->escape($data['href_product']) . "', instructions = '" . $this->db->escape($data['instructions']) . "',
        ]]>
      </add>
    </operation>
    <operation>
      <search index="0" error="skip"><![CDATA[
        public function getProducts($data = array()) {
      ]]></search>
      <add position="after" ><![CDATA[
        $exist = $this->db->query("SHOW COLUMNS FROM `" . DB_PREFIX . "product` WHERE Field = 'features'");
        if (count($exist->row) == 0) {
          $this->db->query("ALTER TABLE `" . DB_PREFIX . "product` 
          ADD COLUMN `features` TEXT CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
          ADD COLUMN `specifications` TEXT CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
          ADD COLUMN `documentations` TEXT CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
          ADD COLUMN `href_product` TEXT CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
          ADD COLUMN `instructions` TEXT CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL
        ");
        }
      ]]></add>
    </operation>
  </file>
<file path="admin/controller/catalog/product.php">
        <operation error="log">
      <search>
        <![CDATA[
          if (isset($this->request->post['model'])) {
        ]]>
      </search>
      <add position="before"><![CDATA[
          if (isset($this->request->post['features'])) {
            $data['features'] = $this->request->post['features'];
          } elseif (!empty($product_info)) {
            $data['features'] = $product_info['features'];
          } else {
            $data['features'] = '';
          }
          if (isset($this->request->post['specifications'])) {
            $data['specifications'] = $this->request->post['specifications'];
          } elseif (!empty($product_info)) {
            $data['specifications'] = $product_info['specifications'];
          } else {
            $data['specifications'] = '';
          }
          if (isset($this->request->post['documentations'])) {
            $data['documentations'] = $this->request->post['documentations'];
          } elseif (!empty($product_info)) {
            $data['documentations'] = $product_info['documentations'];
          } else {
            $data['documentations'] = '';
          }
          if (isset($this->request->post['instructions'])) {
            $data['instructions'] = $this->request->post['instructions'];
          } elseif (!empty($product_info)) {
            $data['instructions'] = $product_info['instructions'];
          } else {
            $data['instructions'] = '';
          }
          if (isset($this->request->post['href_product'])) {
            $data['href_product'] = $this->request->post['href_product'];
          } elseif (!empty($product_info)) {
            $data['href_product'] = $product_info['href_product'];
          } else {
            $data['href_product'] = '';
          }
        ]]>
      </add>
    </operation>
  </file>

Accordingly, how to make it possible to add an array? href_product[0][name], href_product[0][href]