Hello, I bought the book to learn the SilverStripe works a bit like this platform. I'm new in this world of programming. My question is here, I created this code through the book and the tab does not appear Jobs

function getCMSFields() {
$fields = parent::getCMSFields();
$jobsTable = new ComplexTableField($this, 'Jobs', 'Job');
$fields->addFieldToTab("Root.Content.Jobs" , $jobsTable");
return $fields;

}

mysite/code/JobCategory.php

someone help me?

Is that code called at all? If you put a 'die()' in there does it break and kill everything? If it doesn't then that function isn't even being called. Check the type of the page in the CMS, also make sure that function is in the JobCategory class.