Auditing existing infrastructure advice

I got picked up by an IT team because im focusing my career development on cybersecurity.

While its not a cybersecurity title, most of these projects are moving in my direction. The previous sys admin was... disorganized to say the least.

So, Im brought on a team without the original person that setup this infrastructure, and while the general network hardening practices look like they are well followed; I have no idea how to start auditing and cataloging all the …

admin advice auditing career career development cybersecurity development infrastructure it team moving projects setup team