Your little guy is at a weaning age, and he needs to spend more time in his cage, learning to eat. He should be eating a lot of food on his own already. Most cockatiels in captivity are fully weaned by now. The noise he is making is a begging noise. That’s why he isn’t interested in being handled – he wants to be fed again. What you need to do is put a lot of food in his cage first thing in the morning, before you hand feed him. Put dishes with pellets, warm soft food like cooked brown rice with mixed veggies, some chopped fruit, cooked eggs, and fresh water. You can mix some thick formula and put that in a cup for him to eat on his own. You should then leave the room and go where he can’t see or hear you for about an hour. Then come back, check on if he has eaten anything, and feed him some formula. Don’t stuff him, or he will have no incentive to try the food. Leave him alone again so he can digest some of the formula, and he might even pick at some food. Repeat this before each feeding. He should soon be eating enough that you will cut one feeding at a time and eventually stop handfeeding. You can still handle him some, but if he starts the screeching, put him back in his cage. Don’t keep him out when he screeches. Not only are you teaching him to screech to get attention, but it is also exhausting for him.
Thank you for asking Lafeber,