If you look in Linkedin and other job portals, most companies look for DM interns, not stable employees. Plus, most Digital Marketers out there have no degrees in Digital marketing itself. They are just regular marketers who have aced technology.
No, you don’t need any certificate for that. There are many companies that will offer you Digital Marketing jobs despite only having a graduate degree. U just have to find your perfect fit and keep trying to land the best job/ internship u can.