Salesforce - Send Email template with Apex Coding

//Email will be sent to target object's email

public static void sendEmailTemplate(EmailTemplate p_etemplate,String targetObjectId){
        Messaging.SingleEmailMessage message = new Messaging.SingleEmailMessage();
        List<String> emaillist=new List<String>();
        // emaillist.add(email);
        message.toAddresses = emaillist;
        //message.ccAddresses = new List<String> {label.Off_Boarding_CC_Email_addresses};       
        message.setTargetObjectId(targetObjectId);
        message.setSenderDisplayName('Lead Sales Process');
        message.setUseSignature(false);
        message.setBccSender(false);
        message.setSaveAsActivity(false);       
        EmailTemplate et=p_etemplate;           
        message.setTemplateId(et.id);       
        Messaging.SingleEmailMessage[] messages =
            new List<Messaging.SingleEmailMessage> {message};
                Messaging.SendEmailResult[] results = Messaging.sendEmail(messages);       
        if (results[0].success) {
            System.debug('The email was sent successfully.');
        } else {
            System.debug('The email failed to send: '
                         + results[0].errors[0].message);
        }
    }