I did the SCR with GARP.
I work in Finance and ESG qualifications are really getting lots of attention.
I recommend starting with GARP SCR, as you can do it an a few months, it is not expensive and since you have to take a 3 hours exam on it, it is also more appreciated by employers and recruiters, because they consider it a certified achievement and GARP is well known.
You can study with the material you get from GARP when you enrol in the program, but it is super heavy and lots to study. I used the summaries in https://docmerit.com , search for the course “Sustainability and Climate Risk – GARP SCR- Summaries and notes” . Worth the money if you don’t feel like studying 750 pages and + recommended reading.