CNA question, please help?

I'm 16 and live in California and I want to take a CNA course. I've read online that you can take the course when you're 16 but on other websites I've read that you have to be 18 to take the course. so I'm confuse, do I have to be 16 or 18?? And another question, do you absolutely HAVE to have a clean criminal background or is it okay to have one little crime that happened years ago?? When I was 13 I made a stupid decision to try to steel something from a store and I got caught -.- but I payed off the whole fine now and I never stole anything again :)