Welcome, and that sounds like a noble goal. I would start by looking at what you want from your certification/certificate. Remember you need to pay AMFs and keep up CPEs for certification:
https://www.isc2.org/Membership/manage-membership
With your experience It would be likely better to look straight at the CISSP or perhaps SSCP as a warm up, as with 20 years in IT I can’t imagine CC providing you anything that you didn’t already know, or even being much use but it’s definitely easier to obtain.
if it’s an internal goal/KPI I’d start with SSCP or CC as that’s in your control and CISSP would need to look at lengthier experience in the domains, also if certifying it might take longer so do write it as pass one of the exams. Cost for exams and training vary as well, so do factor that in.
There’s a plethora of trining out there from iSC official, to boot camps, online and quite decent resources on linkined in learning, plural sight, demystify etc - though frankly your experience and one or two books are probably your best friend.
Read the CBK, the exam outlines etc.
For a sponsor try to find an ISC2 member you know/work with much easier to verify your experience etc.
