I have a 14 weeks old hand raised alex (call Ozzie) that I got 4 weeks ago. For the first week he has been very aggressive and bites hand that goes near him. After I started training him, he has never use he's beak ever since then.
It sounds like that your alex doesn't fully trust you, the number one biting reason in pet bird is caused of fear.
I recommend you start target/touch training him. You'll need a chopstick (or a non toxic stick), a clicker (which you can find in pet stores. But as far as the clicker goes, you can just use the word good) and some treats that he likes.
Anyway, you put the chopstick in front of your Alex to show him, and every time he touch the end of the chopstick GENTLY with he's beak, you gonna click the clicker and reward him a treat. If he bites or attack the chopstick, do not reward. But if he does attack the stick, you can mash some berries so you can put on the end of the stick, so next time when he tries to eat the berries by gently touching the stick, reward him. He will quickly learn that when he touch the stick gently, he gets a treat. Once he knows what to do, then you can start targeting him to climb in and out of he's cage.
So what target training does is that it is a great way to bond with your parrot using positive reinforcement. It also teaches him that hand isn't scrary. So next time when he doesn't step up, you can target him up onto your hand. And when he won't go back into he's cage, you can also target him back into hes cage without being scared to be bitten.
Once he is used to target training and is very good at it, you can start teaching him tricks with a target stick, like turn around and flight training.
The important of positive reinforcement is that I don't recommend you force your Alex to do anything he doesn't want to. Just say if he won't step up, give him a little bit of time and try it later.
If you have anymore question about target training, feel free to ask me.
Happy new year.
