Co-Worker's behavior

So ive been in IT field only 5yrs and I got an entry-level cybersecurity job recently (4months) . Im having this problem with one of my Co-workers that thinks hes a know it all and always giving me jokes of how I got this job, I should be in a less-level and how much I dont know much about security. It makes me insecure of moving forward in this field (even tho I really like it and want to learn …

cybersecurity cybersecurity job entry job jokes problem worker workers