Cockatiel making weird noise everytime I scratch or take her away from her food

The way I understand, you have her for only a few days / weeks. That is usually too short for the bird to learn to trust you and befriend you.

On the other hand (if the video is with your bird, not something random from the net) the bird is actually trying to communicate with you. If you do not understand whatever she is saying, it is your problem :)

Joke aside, just continue to be friendly and in time you will find a "common language".

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I had in the past that kind of cockatiel, and it enjoyed making loud whistle-like noises. Especially in the morning, before the alarm was set to wake us up. That is life.

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Advice: only provide food in her "house", in the proper place. For your long-term better life ;)

Guess: she might be angry with you for spilling the food in the improper place. ;)

It isn't surprising that your bird is upset, since she's still very young and is in a completely new place without her previous family. I've had new cockatiels who screamed when they were new to my home. It takes a lot of time, patience and--especially--attention while she builds a bond with you and feels secure in knowing that you will not leave her.

The weird noise is a begging call. Be sure that she has a rich and balanced diet. She's very young and still growing, so she can easily be short of some nutrients even if she's eating a large quantity of food. She's still a little young to be completely weaned. If you can get an avian hand-feeding formula, it might help. She's too old for a syringe, but you can mix it up (room temperature) and feed her with a small spoon. It will help ensure that she gets all of her nutrients.

Remember that the whole world is still new and scary to her, so she's going to be a bit freaked out for a while. That's okay. Patience and love will make her feel better gradually.