He does not respond to me at all really
For example; he doesn't answer to his name. I know he isn't just ignoring as I can see his face, no recollection is traceable. I know he isn't death because he will respond to the sound of a crisp packet or Peppa Pig being put on.
He does not point, won't follow my finger or respond to me if I point. He won't respond to anything suggestive, not even something extreme such as 'OMG look at that! Wow!'.
This all makes working with him extremely tiring. I feel so bad for complaining like this
He's such a beautiful boy. But it's just everything I can think of to help him doesn't work as there is 0 engagement, I get nothing back. I can't read a book to him or show him something. It's not even that he's ignoring me, it's like it just doesn't register with him.
He does not play. Will not acknowledge other children his own age/older at all. It's like they are not there. He will remove himself from the situation if a child tries playing with him/alongside him.
He doesn't do imaginative play. He won't pretend to feed a doll or answer the phone, for example. Not interested in it anyway.
The only thing he does is stack and put away. Stack and put away. He likes to build blocks or lines toys up, then put them away, then get them out again. He won't do that with bath toys though, he has a bucket full. If you put the bucket full in and leave the bucket by the side, he will promptly put them all away and look a bit miffed that they were put in his bath water 
He likes to stack food ifnits something like waffles etc. He will stack, unstackand eat one, then stack again. On repeat until the meal is finished. He is otherwise a fantastic eater and likes food.
He does have some eye contact, for example we often bath together and he likes for me to play 'where's bubba?'. He looks at me in the eye with his big beautiful eyes. But he won't copy me/play ball. Just likes to watch. I don't get any eye contact otherwise during the day.
He makes odd hand/finger twiddling when he's a little bit embarrassed to see someone (he usually only does this for his aunty). She will bellow in a loud voice HELLOOO YOU! And he will smile and bend his neck, and hand twiddle. He's done this before for me too, when I've brought food out to him.