It’s good that you are doing your research first. While both are a species of parrot, there is a world of difference between a Cockatoo and a Cockatiel. Besides being significantly larger & louder, Cockatoos are a much more challenging bird than a Cockatiel, and really not the best choice for a novice. A Cockatiel is a much better choice as a first bird. However, you need to understand more about parrot behavior before you decide to get one. There is no guarantee that any bird you choose will be a good pet with an entire family. Young parrots interact with other young parrots in the flock, but once they become mature, they will choose a mate and from that point, only closely interact with the mate. With a pet parrot, you want to socialize the bird with everyone in the family while it is young, and ideally it will remain tame with everyone. But when it gets mature, if one person tends to handle the bird more than anyone else, there is a chance the bird will begin to favor just that one person. This is why it is important to limit petting from the beginning to the bird’s head and neck, and avoid petting the bird on the body or cuddling with it. When you pet a parrot on the body or let it cuddle with you, you are sending the signal that you want to be a mate.
Parrots are not a domesticated pet like a cat or dog. So you have to take their natural instincts and behavior into consideration when handling and training a parrot. This also brings up your plan to get two birds. Two birds caged together are not going to remain tame. Even if they are the same sex, they will eventually bond with each other and no longer want to be handled by humans. When you have a parrot as a pet, you are the bird’s companion. He doesn’t need a bird companion – you are replacing another bird as the companion. It’s OK to have more than one bird, but each bird needs its own cage if you want them to remain tame.
I would recommend a hand fed Cockatiel, Lovebird, Budgie or even a Green-Cheeked Conure as a first bird. Do your research and buy the bird from a reputable breeder or pet shop. While you may read a lot about adopting from a rescue, keep in mind these birds are often abandoned because of behavioral issues and most need an experienced bird owner and not someone looking for their first bird. It is very important that you can handle a bird before you buy it. If the seller won’t let you handle the bird, go somewhere else. If the bird isn’t tame at the pet shop or breeder, it isn’t going to be tame when you get it home. Ideally you should be able to visit the bird a couple of time and handle it before making the decision to buy it.
Thank you for asking Lafeber,