Need help proofreading
A couple of notes from the first paragraph:
only bed and closet for furniture. Inside the bathroom were sink, shower, and toiler made of wood. The cold water on his face woke him up completely. the boy looked at his reflection on the mirror.
A toiler is someone who toils. You might be looking for toilet.
Note that you use a capital letter on the first word starting a sentence.
Big languid black eyes, raven short hair, plumb cheeks with baby fat, slender still growing body, and white skin. Combine all that and you got a boy to... I mean, a healthy boy. the 12 years old boy were wearing a loose one-piece azure-colored robe, he combed his hair to the back with both his hand and changed his clothes to a black long pants, white shirt, and blue robe with a cat-eared hoodie.
The green bit: 12 year old boys don't have baby fat anymore. You could get away with it at age six or so, but after that there have been several growth spurts that burned away any traces of pudginess in the face. At age 6 round about the face starts to really develop and lose the round features it has, and the individual sharp contours start to develop on children's faces. Noses turn less round, cheeks lose their pudginess and eyebrows start to become more defined.
My suggest would be to let it be at plumb cheeks and drop the with baby fat part.
The red bits: Capital letter after a dot. Were should be was. Were is for a plural, a group of boys. The boy is singular.
The blue bit: You move from a descriptive sentence about the appearance and clothes of the boy, to an action sentence where you describe what the boy is doing at that moment. Place a dot between those, not a comma.
The orange part: What? How? Where did the clothes come from? What did he do with the azure robe? was that a sleeping gown? Were the clothes already in the bathroom? Did he bring them? What did he do with the azure robe?Did the combing the hair back cause the change in clothes? All in all a very strange turn of events as it's currently written.
I suggest you re-read your own story sentence by sentence critically, and throw it through Grammarly. It found 16 grammatical errors in your first chapter. 55 in your second chapter