That's an extremely bad case of splayed legs, one of the worst I've ever seen...There is NO WAY you should have paid $200 for a Green Cheek Conure who was obviously not at all hand-raised and has a permanent disibility...You need to call that breeder and ask them what gives, as splayed legs is a result of the bird not being on flat ground, and of not perching...So my guess here is that this breeder #1) Doesn't hand feed at all or interact with their babies, and just lets them/forces them to stay in an uneven nest box, or probably, unfortunately, a cardboard box, and #2) Did not put him in any kind of weaning cage, meaning he never learned to properly perch either, which is why he's simply sitting on the bottom of the cage, poor little guy...
It seems he is weaned at 8 weeks if he is eating seeds, fruits, etc., but yes, he should be on diet of pellets with a fortified seed mix supplementing it, and then lots of daily fresh veggies and fruit. But at least the bird isn't still on formula, though this is not at all due to a good breeder, but only happened by accident or chance because the breeder doesn't hand-raise and allows the parent birds to both feed and raise the birds completely, and PARENT-RAISED BABIES WEAN MORE QUICKLY THAN HAND-RAISED BABIES, AS THE PARENTS STOP FEEDING SOONER THAN WE HUMANS DO...
However, the problem is that this breeder did not provide a proper living environment for the babies as they hatched and grew, and this is why the splayed legs happened...
I'm sorry, but at 8 weeks old it's highly unlikely that leg splints will help much, maybe a little bit, but at 8 weeks his leg bones have almost fully developed. To fix splayed leg, you have to catch it between 4-6 weeks or earlier, get the splints on, etc. AND IT'S ALSO HIGHLY LIKELY THAT SINCE THIS BREEDER IS NOT A GOOD ONE AT ALL, AND BECAUSE HE IS ALREADY SEEMINGLY FULLY WEANED, THAT HE IS ALSO OLDER THAN 8 WEEKS OLD!
That would be my best guess, as a former Green Cheek Conure breeder for years, that this breeder not only charged you $200 for a non-tame, parent-raised baby that was not raised in a proper environment and who has a permanent disability, but that this breeder also lied to you about the bird's age, and he or she, most likely a female, is probably closer to 12 weeks old. That's my guess based on all of the details given, the degree of the splayed legs, the fact that he is fully weaned, that he's already aggressive and biting, and based on his appearance, I'm guessing around 12 weeks old...
Just to explain to you why I'm raving mad right now, not at you of course, at the unscrupulous breeder who has no business breeding birds at all and who did this to this poor, sweet little Green Cheek, it's because you can buy a sweet, loving, fully hand-tame Pineapple or Cinnamon Green Cheek Conure that was hand-raised by a responsible breeder from 2 weeks old, and who does not have a permanent physical disability for $200!!! That's why I'm upset for both you and the poor baby...
You should definitely talk to a Certified Avian Vet only and try a leg splint or whatever they suggest (make sure it's only a Certified Avian Vet who has experience with splay legs and with Green Cheeks, because an Exotic's or General Vet isn't going to be able to help you much or be able to give you much information about your bird at all), but it's likely that this baby is already too old to reverse the splayed legs much...I hope that I'm wrong...
And I would be calling that breeder ASAP and asking them why in the world they thought it was okay to sell you a baby Green Cheek with a permanent, physical disability...I hope to God they didn't also lie to you and tell you that this baby was hand-raised or tame. And I certainly hope that the rest of their babies aren't also suffering from the splayed legs, but chances are that if they are not providing the babies a proper nest box or weaning cage at the appropriate times that all of their babies have this issue...
