Please refrain from giving your little hatchling/baby beardie mealworms....they are a very poor feeder insect for little young beardies because they are very high in fat and have a very hard to digest exoskeleton (which can block their plumbing up an result in impaction (severe constipation).
Crickets are fine so long as they are suitably sized for the hatchling , gutloaded with calcium rich greens (buk choi / puk choi are good) and dusted (LIGHTLY) light with calcium powder daily.
Other very good feeders for a small hatchling are
>>>> BSF maggots (sold as phoenix worms in the USA) --- an EXCELLENT STAPLE feeder insect
>>>> silkworms (a small hatchling can handle small silkworms (about 1.5 inches long) ---- ALSO an EXCELLENT STAPLE feeder insect.
>>>> blow fly gents (high in calcium but pupate fast !)
>>>> roaches (see crickets).
he is probably stressed by the change in his situation and the tank, new house, new humans, new routine (lighting, feeding and new human routine) ,new sights and sounds around him = all very scary for little hatchling who will also be used to have other hatchlings / siblings around him and is now likely alone in big area (the tank) for the first time in his life.
He is probably also being offered new foods and different feeder insects to what he's accustomed to.
Fear not, he'll soon adjust to his new situation and will soon become very curious about everything and will be basking, studying you, and interested in his bugs (he wont starve himself). We'll soon be hearing from you complaining that he's eating you out of house and home, and costing you fortune keeping him supplied with live bugs.... LOL
Ideally for a very young hatchling the feeding routine is three live insect feeds per day, as many as he wants offered a few at a time (don't just dump a tub of crickets in his tank with him - most of them will hop away and scurry away to hide before he can catch and eat them).
Handfeeding is OK too if he's a stubbornly refusing the bugs you have for him, it's a great way to bond with a lizard.
Continue offering some fresh greens everyday but don't stress if he shows no interest in the greens at this point , is much more important he get lots of high quality insect proteins and fats and dietary calcium for now.
You need him to warm enough (recommend about 40oC - 42oC at the basking spot), and coolzone temp about 28-30 oC.
He needs EXTREMELY high levels of UV ( UVA and UVB ) , equiv to UVI > 13 , and so please check the UV source is close enough, high enough wattage, unscreened, and rated to produce AT LEAST 30% UVA and 10% UVB.
Good idea to start weighing him weekly and keeping a record if his weight and to keep a good log of other things he does daily and to track his feeding too.