I need to add groups fieldset or bundle fieldset with “Add Row” section. like – $form = $this->_formFactory->create(); $form->setHtmlIdPrefix('custom_'); $customerId = $this->_coreRegistry->registry( RegistryConstants::CURRENT_CUSTOMER_ID ); $storeid = $this->_storeManager->getStore()->getId(); $fieldset = $form->addFieldset( 'base_fieldset', ['legend' => __('Details')] ); $fieldset->addField( 'percentage', 'text', [ 'name' => 'percentage', 'data-form-part' => $this->getData('target_form'), 'label' => __('Percentage'), 'title' => […]