Baths aren't necessary unless they get soiled and need to be cleaned off. Some of them are stressed out by baths and it's not worth the stress. Others enjoy a
bath and swimming around a bit. In those cases, you can offer them baths whenever you want. It's kind of a unique choice for each dragon. He will get most of his
hydration from fresh veges and live bugs, but you can offer extra water by dripping it on his nose to lick up. If he is
thirsty, he will tilt his head forward and lick at the water drops. Some of them will drink from a bowl. Sometimes it takes training by flicking at the water to create movement and grab their interest. Others don't drink from a bowl, and that's OK as long as they are eating well. The best indicator of
hydration is to look at their poop. If there is excess water coming through and the poop and urate looks
hydrated, that's a good sign. If the urate looks dry/chalky then it may indicate that some extra water is needed.
The amount he eats will vary. They eat more when they hit a growth spurt. And will often eat less during a shed or in between growth spurts. Offer a salad every day and a couple of bug meals per day up until about a year old. Then slowly taper down to 1 bug meal per day and then 2-3 bug meals per week by 18-24 months old. Adults should be eating mostly veges, but that is often a gradual transition. This is just a general guide though and each dragon will vary a bit. The key is to offer as much variety as you can in order for them to get plenty of nutrients. Having staples on hand that they like is good, but swap in some new stuff once in a while that's all.
The visible lights (basking light and
UVB light) should follow the pattern of the sun and be off at night. If the temps inside the enclosure stay above about 65 or so overnight, then no additional heat is needed. If the enclosure gets colder than that, you can use a heat projector or ceramic heat emitter which will provide heat without visible light (which would disturb their sleep). A bit of a cooldown overnight is natural for them. You don't need to bump the heat much overnight. Just into the high 60s or low 70s is good.