I would not use a glove. If he trys to bite you when giving a treat by hand he isn't ready to take a treat by hand and you are rushing him.
Plus as you've heard already, everything is going to be more difficult with such a small cage. As he is trapped with little room to choose to retreat over bite. Plus there is constant stress to him in such a small cage.
Instead get a tiny treat only dish. Show him the treat, ask him to come here. Drop the treat in the treat dish. Then take 2 steps back and ask him to come here again. Every step he takes towards treat dish tell him good bird. When he takes treat from dish really praise. Repeat this many many times a day.
When he is at the point he feels comfortable coming quickly to get the treat from the dish, then you csn only take one step bsck from dish . This is shaping, and building trust , and breaking things down to little steps. That kind of approach is very successful with parrots.
After several times of him coming quickly to take treat when you are one step away from dish. Then you can move to the next step. Standing right next to treat dish show him the treat ask him to come here, put treat in dish. Big praise when he takes with you Standing there. Now do that lots during tge day.
After that you can go to holding the treat and asking him to come here. Wait till he is right next to dish and then drop treat in dish. Again repeat lots.
The next step is to ask him to come here holding the treat by the dish. Abd yiu kerp holding as he comes over and hand it to him. By this point he should halve trust in the process. Trust that yoy aren't going to do anything shady. His brain has already learned moving towards you equally treats. So I should take from you with out bites.
The temptation is always people want to rush through these steps instead of taking the time. But it's important to build layers, to have the repetitions, to build trust. So don't skip the steps.
It's fluid when working with birds, and you will increase your skill at reading him and him at reading you. Showing him you respect him and that he doesn't have to bite you to get you to respect him.
The method I shared works. It has worked for me with a wide range of species , many more than I currently have. Including wild caught and aviary birds.
There are probably lots of other ways. Including the target training as mentioned. And it is probably very helpful to watch videos rather than reading.
Plus its labor intensive for me to write out each little step.
I will go ahead and share the next step after taking treats from hand nicely. That will eventually help you with step up. Hold your other hand the step up hand, outside of the cage bars in the step up postion, but far enough bsck he csnt bite through the bars. Then start handing the treat over thst hand to him. Again many many times . Until he is no longer nervous about that hand being there when you hand threats over it. Then you can move the hand until it is pressed against the bars in step up position just below tge middle of his chest, and hand your treats over it to him. This will really set you up for when you being step up training for real. As he won't be nervous about thst hsnd being near him. Its already associated with treats.
