Hello! I am new to this wonderful community and need urgent help with my Alexandrine parrot.

I bought him yesterday from a regular pet store, where he was not in the best state. He was in a small cage for his size, had only sunflower seeds to eat from, no toys, and the cage was placed on the floor for almost his whole life. He is around 2 years old and it was very stressfull for him to move him from the pet store, all the way to my home in his new cage. He shrieked like crazy, hes was very scared of humans at the pet store (would move away from the person in his cage), bit the pet store workerwhen he handled him with a towel, and was breathing rapidly.

When we arrived home we moved him from the small cage to his new home, a big wide cage, where he is able to extend his tail.
Yesterday after an hour of being in his new home, he seemed to me moving around side to side on the highest perch in the cage, and has not moved from there since.
Today, this morning I've been coming in and out of the room he is in, and has become comfortable with me in the room. Now he does not move away from me when I get close to the cage. I can talk to him move my hand slowly towards him and does not fly in fear to the other side of the cage.

THE PROBLEM: I understand it is a new environment, everything is new, and he has not moved from the top perch. The food and water bowls are lower in the cage, and has not eaten or had any water but seems very curious. I try giving him food through the cage, but slowly walks away. What should I do? Should I move the food/water bowls to the top perch?(he gets very scared if I stick my hand in) Should I stick some fruit on the cage where the perch is? I dont know what to do and am really worried for him if he does not eat. I want to give him a new life, a better one than the one he was in before.
Thank you and I would greatly appreaciate any help, any questions, anything.