I'm a newbie to beardies too (not to reptiles so much, we're having more than 20 snakes), and from what I already can see on my example:
At first we bought a 2 months old female, and in my opinion it's a perfect age for someone without experience. They are still young so you can "teach" them everything, but they aren't as fragile and jumpy as totally little ones.
My second was a 2 months old male, so basically the same.
And my third is a 1 month old hatchling. She's super cute, but a lot harder to bond and tame, mostly couse hatchlings are very afraid of everything, super jumpy and really fragile. With some experience from our bigger beardies I can manage her somehow, but without it I would be totally lost as to how to pick her up without hurting her etc.
So, if you want a "baby" that will already be more confident and not as fragile I really recommend you look for 2-3 months old beardies