If your bird is biting you, I'd suggest using other online resources and reading training/bird handling articles BEFORE asking a question that you could've found hundreds of solutions and answers to. I don't mean to sound harsh, but it's so stressful to see all the people inadvertently training their birds to be "bad" because they don't have knowledge of avian behavior or body language! Birds don't bite or scream without a reason (or prior conditioning) to do so. In edition, hitting, mutilating the bird's bill, flicking, yelling, etc will all make the situation worse and cause further strain on your bird. Keep in mind you literally have a wild animal living in your house ("tame" and "domesticated" are two very different things) and their main goal in life is not to please YOU ( like a doggo). Before you go to extreme measures to try to "fix" your bird, be sure all its requirements are being fulfilled (adequate food, water, security, space, nutrition, emotional and mental stimulation etc). There are a few reasons birds scream, and just a little research would make it very clear its usually for attention. Youtube has some amazing resources for bird training! I know this post probably won't help you directly in changing your bird's behavior, but I hope it got you researching your questions! Some great youtube bird training channels include: parrot wizard, parrot whisperer, birdtricks, Dave Womach, Manda & Rio, and so many more!