What Certification should I look into to help others budget and invest?

Early 40s, F. I have a successful career in Medical Sales, long term investor, heading into early retirement and thinking about a “for fun” retirement part time gig. I’m starting to help a lot of my girl friends who are also successful professionally (200-400k ish income range) but dont understand investing to learn basic things like what a brokerage account is, what index funds are, importance of maxing out 401ks, HSAs, IRAs, etc, and am loving it. What certification should I look into if I wanted to advise on budgeting, retirement planning, and basic investing? I’m kinda just shocked at how many people I know have great jobs but dont put much thought into investing, they just spend spend spend.
Only interested in a model that charges for time, NOT anything that takes a % or funds invested of offers commissions.

Thanks in advance!