This and much more should have already been covered in books you've read or information you found on the internet.
First thing you need to do is have your bird examined by an Avian Vet in your area. This has to be done before any taming or training can begin. A sick bird cannot do the work of training, so please don't try and make it.
The other issue is you have to earn a bird's trust as it is never freely given. This means you have to spend lots of time cleaning cage and feeding bird for him to start to trust you. It will not happen in a few days as your bird is not a toy and is a real live creature with feelings both emotional and physical you need to learn about.