can masterbation delay puberty
Definitely not. Mast*rbation has no effect on puberty whatsoever. It doesn't cause any harm at all. It's also nothing to be ashamed about because many teenagers do it (and some either younger or older). Ask any doctor you like and they should tell you that it's a perfectly normal thing to do.
...as far as I'm aware you can't masturbate to orgasm until you reach puberty. or at least, I wouldnt think someone under the puberty age would even be interested in masturbation.
Masturbation if causing anything will speed up the proccess of adolescents/puberty.
No. Puberty arrives when its ready to.