I got a male veiled chameleon about a week ago and I have done a lot of research but I still have some questions. How do I tell how old he is?
For sure? You don't, unless you got him from a breeder that can tell you his hatch date. Some here can guesstimate with a picture—try to include a reference, like putting a ruler (or something of common known size) behind him.
How much calcium should I sprinkle on his food?
Very little. He'll be getting it every day, and it's to supplement what he'd get from his diet, so a light
dusting—not a
powdering. Some use a plastic bag; I prefer a small plastic container (You can usually get a stack of them at a dollar store). Add a tiny pinch of dust and shake.
Are mealworms ok to feed him bc I've heard that they're bad and that they're good.
They may not be the absolute best thing, but they're not the worst, and they're
definitely better than nothing. I prefer to feed giant mealworms; they get bigger and keep longer—just the thing if you run out of crickets or roaches. I always keep some on-hand, and feed a few a couple times a week.
What are some beginning signs of mbd?
MBD can take weeks to months to develop. The most common cause is poor husbandry.
Early symptoms of MBD include bowed or swollen legs, arched spine, bumps along the bones of the legs, spine and tail, bilateral softening of the jaw (commonly referred to as rubber jaw), and softening of the carapace and plastron in turtles and tortoises.
https://avianandexoticvets.com/metabolic-bone-disease-in-reptiles
And finally I've heard that hand feeding is a great way of bonding with him but I do not really like the idea of putting insects on my hand so is there any other good way to bond?
Is the problem mysophobia or the creep factor? If the former, insects—particularly farmed insects—are probably cleaner than your chameleon, and in many cultures insects are increasingly becoming part of peoples' diets. If the latter,
in the nicest possible way, get over it. Crickets, roaches, worms, etc. occasionally get dropped or otherwise escape, and the fastest way to recover them is just reach out and grab them. Feeder insects don't bite, and if it bothers you that much, you can always don some surgical gloves.
You can tame/handle without them, but it will likely take longer.
Either way, best practice is washing thoroughly after handling any reptile (we all know how to do
that now!); a few insect germs (albeit less likely) shouldn't make a difference.
IDK if "bonding" is the right word. As far as establishing trust for handling purposes: