I have been working in IT industry on different job profiles(2008-2021), starting from roles like:
I am a graduate in IT, with Bachelors Degree. And also, currently I am pursuing my PG certificate course in Cybersecurity.
Is this experience and education sufficient to meet the work experience requirement for getting myself CISSP certified after clearing the exam?
Your Bachelors Degree will count as 1 year working experience waiver.
it's not your job role but your job duty or job experience is falling into 2 or more domain listed in the 8 domains.
https://www.isc2.org/Certifications/CISSP/experience-requirements
and you need the 4 years of the working experience.
It would be worth you re-examining the content of your role as system administrator in terms of how it matches the domains and how long you did the role for.