Unlike automotive mechanics, plumbers, and electricians, there is no credited classes or programs. Of course, independent training classes do offer a certain type of certification, but it holds no weight, it’s simply merely to make it feel more “real.”
If you’re interested in getting started in auto detailing (assuming you want to either get a job as an auto detailer or start your own business), then you can simply start learning on your own.
Although I will say that being an auto detailer does not have the same benefits as other service-based industries in terms of what they offer to employees.
From what I’ve seen, auto detailing companies pay a low-wage and are not to worried about quality.
You can always start your own business if that’s what you’re interested in, but that’s a whole other topic entirely.