Parrots are smart animals and can learn many tricks. At least that's my experience with our cockatiels.
Our problem is not teaching the birds how to do certain things, but teaching them not to do some bad things, such as not to bite any kind of wires, not to touch keyboards, not to fly to dangerous places, etc.
I read several times that unlike with dogs, negative reinforcement or punishment doesn't work well with birds and should be avoided. What is then an effective way to prevent certain behaviours?