php – Send different email template to customer


I have a custom module which is a custom form for the user to book an appointment, this form works fine with no issues, the form once submitted sends and email to both the admin and user/customer but it uses the same template but what I’d like is the customer to receive a different email with a success message etc.

I have this is my email_templates.xml

<?xml version="1.0" encoding="UTF-8"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Email:etc/email_templates.xsd">
 
    <template id="video-appointment" label="Video Appointment Form" file="video-appointment.html" type="html" module="VideoAppointment_Appointmentform" area="frontend"/>
    <template id="video-appointment-customer" label="Video Appointment Success" file="video-appointment-customer.html" type="html" module="VideoAppointment_Appointmentform" area="frontend"/>
     
</config>

And I have this in my Post.php file

public function execute()
    {
        $post = $this->getRequest()->getPost();
        try
        {
            // Send Mail
            $this->_inlineTranslation->suspend();
            $storeScope = MagentoStoreModelScopeInterface::SCOPE_STORE;
             
            $sender = (
                'name' => $post('name'),
                'lastname' => $post('lastname'),
                'email' => $post('email'),
                'phone' => $post('phone'),
                'byphone' => $post('byphone'),
                'bytext' => $post('bytext'),
                'byemail' => $post('byemail')
            );
             
            $sentToEmail = $this->_scopeConfig ->getValue('trans_email/ident_custom1/email',MagentoStoreModelScopeInterface::SCOPE_STORE);
             
            $sentToName = $this->_scopeConfig ->getValue('trans_email/ident_custom1/name',MagentoStoreModelScopeInterface::SCOPE_STORE);
             
             
            $transport = $this->_transportBuilder
            ->setTemplateIdentifier('video-appointment')
            ->setTemplateOptions(
                (
                    'area' => 'frontend',
                    'store' => MagentoStoreModelStore::DEFAULT_STORE_ID,
                )
                )
                ->setTemplateVars((
                    'name'  => $post('name'),
                    'lastname' => $post('lastname'),
                    'email'  => $post('email'),
                    'phone'  => $post('phone'),
                    'byphone' => $post('byphone'),
                    'bytext' => $post('bytext'),
                    'byemail' => $post('byemail')
                ))
                ->setFrom($sender)
                ->addTo($sentToEmail,$sentToName)
                ->addBcc($post('email'))
                //->addTo('owner@example.com','owner')
                ->getTransport();
                 
                $transport->sendMessage();
                 
                $this->_inlineTranslation->resume();
                $this->messageManager->addSuccess('Thankyou for your appointment booking request, we will be in contact with you shortly.');
                $this->_redirect('video-appointment/index/index');
                 
        } catch(Exception $e){
            $this->messageManager->addError($e->getMessage());
            $this->_logLoggerInterface->debug($e->getMessage());
            exit;
        }

I can see the amil template is being set by

->setTemplateIdentifier('video-appointment')

But how do I set another template ie the video-appointment-customer.html so that sends to the customer?