I think I should start to tame Mango now, he has been here 5 months and he is comfortable being near me now but of course if I make any movements he will leave.What training method should I start with? He needs to get over his fear of hands once and for all.He is less likely to fly when I come near him now and will instead jump on my arm.

I'd say get him used to taking treats directly from you first.

I thought of a way to do that in a case like Mango's, but I've yet to try it. Considering one way people teach birds to step up using a perch before they use their heads or arms, than I was wondering: why not do something similar with treats?

Stick the treat on the end of a long stick (I personally think that a ruler would be easier for certain foods), and let him take it off the end while you're holding it. He might be scared at first, but then he will start to get used to it. Once he's comfortable taking the treats from the stick, gradually start to shorten the length of the stick. That way, he will begin to get comfortable taking treats with your hand nearby. Then eventually, you can move from stick to hand.

Once he can finally eat from your hands, the rest of the training should become easier because his fear of hands will be gone.

Good method but what if he never becomes comfortable with the stick?

What you can do is just lay the stick next to him, and let him inspect if on his own. Probably put food on one end while it's laying there, so he can begin to get the concept down.

Ok ill try that

A lot of people use a long-handled spoon to deliver a treat to a hand-shy bird. If the spoon is shiny metal that can be a bonus lol. Another technique is to put the treat down near the bird so he can reach it easily, but don't ask him to actually take it from your hand.

The spoon is a good idea but just putting it near him is not gonna get him used to hands.

It'll get him used to receiving treats from you, and you'll be using your hand to put the treats near him. So he'll come to realize that the hand is a source of good things.

Ive been doing that 5 months he obviously doesn't think that way.

What are you trying to train him to do, specifically?