IAM challenge - Need some light

Hello everyone, I'm looking for some light here on the best course of action whenit comes to getting the control over identity and access management in a new position I just started.

Company about 300 employees, Okta, Google Workspace, MDMs in place, not all perfect configured to fully potential but ok, then it comes the challenge. Just cross matching some data, between Okta and other Softwares registered in FS, the company has around 300 services/softwares/applications, that without counting the very probable shadow IT.

One of the defined goals for this year in IT (and yeah, that will be me) is to get the control over all applications we have, not own them per se, but be responsible for their access, license management, price/contract renewal etc, and I'm a bit lost, I don't know how to tackle this in a efficient way.

We must have around 60/70 applications in Okta which already helps a lot in the access management part, but for a lot or most of the the services I don't have much information and I'll probably have to go after all the information I need the hard way, looking for owners of the applications that are not at all documented.

How would you handle this? Is there any good solution in the market where I could consolidate services information? Something that would both help me control access, audit, and maybe even give visibility to owners about their applications? Or possibly even helping find shadow IT in my organisation?

I've been working in small/medium size tech companies for the last 8y in Europe and I feel every place has this exact same issue.

Appreciate any ideas on the subject!