He doesn't need to drink water at all if his diet is appropriate, beardies in the wild drink little to no water at all, and most pet beardies don't drink water either. He should be getting his
hydration from plenty of live, juicy insects and fresh greens and veggies daily. Most will not drink out of a bowl at all, and leaving a bowl of water in their enclosures overnight can be dangerous if they lay in them and fall asleep, as they often do, because their body temp can drop dangerously low. Since they usually don't drink from a water bowl it's useless to put one in their tanks.
You can try dripping water from either an eyedropper or an oral syringe on his snout, so it drips down over his lips, to see if he'll lick it off. If he does, then continue to drip it, drip by drip, until he stops, and do that 2 times a day. But again, most won't drink it, or if they do it's only a drop or two. Some beardies will drink water while in a
bath, but again, most won't. If you try all of these things and your beardie doesn't drink, it's because he most likely is getting adequate
hydration from his daily live bugs and fresh greens and veggies. This is why you must offer plenty of live bugs and fresh greens and veggies every single day, and absolutely no "freeze-dried" bugs or greens/veggies, or already dead insects, because they contain no moisture.
So again, you can try the drippin method, but if he won't drink that way, or from a bowl or his
bath, it's perfectly okay as long as you're feeding him properly. I had my first beardie from a month old to almost 13 years old, and I never saw him take a drink of water...I would mist his enclosure once a day, making sure I sprayed his fake plants and rocks, maybe he occasionally licked the drops off, maybe not, I never saw him do it, I mainly did that for his shedding, but neither him nor my now 10 month old girl or my 4 month old boy have ever really taken a drink, and they are very well
hydrated.