Lizards are cool, I have one but they are not a ‘pet’ like a dog cat or rabbit.
They will tolerate handling but won’t appreciate hours of being out, passed around countless friends, dropped etc.
As such, from a child’s perspective they can get pretty boring very quickly. Not anyways, but certainly a lot of the time.
Note certain equipment is mandatory – UV light source (for the vast majority of lizards – there are rare exceptions so research first), heat source, thermostat to control heart source, a vivarium of the right size etc.
Quick note on bearded dragons. Great lizards, the most pet like of them all. They will suit in your knee and chill with you. But, only get a single one regardless of what the store may try and flog you. Young bearded dragons are quite hard to sex. Two males will fight, two females may tolerate each other. A male and a female may produce 100 offspring in a single breeding season. What are you going to do with 100 babies?!
Finally, buy from a reputable reptile shop, not pets at home et al. If your anywhere near Sheffield I highly recommend Snakes and Adders. They’ll give you the right advice, won’t all anything unsuitable care wise and can sort you out a complete set up.
If you are not in Sheffield feel free to post here or email me (in profile) and I’ll give you some recommendations. Email also if you have any other questions about reptile keeping in general.