OK, here goes, this is a golden nugget of information for you about autistic children. I have a lot of experience with these kids.
My mom is an autism therapist/assistor at a special needs children center. I'm only 17, and have been around her and the kids alot. I can see you don't know much about Autism AT ALL, and the first thing i want to say is that i strongly reccomend you to see someone about quality help for your lil' guy. He is definatley autistic.
I suggest you study autism on a deeper level (wikipedia, youtube videos) so you understand how their minds are functioning. Their brain will simply not make the connection of 'get your jacket' right away. My mom used to work for a Korean family with an 8 year old autistic boy and he had come a LONG way, (still could only speak in short words, but he had started with only screams/moans/whines.
Only with the help of persistent learning games (such as flashcards, simply worded questions.. etc.) and NOT GIVING IN to when they point at things and moan or whine. That is just teaching them that they can get away with it. They need to learn that by screaming/yelling/kicking, they will NEVER get what they want.
Meltdowns are a part of autism as well, so get used to those for probably the rest of his life (even over the randomest thing).. Still, it's unfortunate that you're so young and so busy.. Having an autistic child is a full time job that is a journey just as much for the parent as it is for the child.
Use flashcards with words and short phrases such as mom, cat, dog, blue, red, green, (all colors), etc, with pictures on them. This will help with vocabulary and connections between words and what they refer to. A normal kids' brain would automatically do that, but an autistic kids' does not.
Also, they learn a lot slower than any other children (and i mean ALOT.), so you will need to constantly say the phrase you want him to repeat. For example: if it's time to put shoes on, you say "(His name) shoes on." and show him where the shoes are. This will probably take many tries to get it down, so staying patient is essential!
Another example: when it's time to eat, (You should teach him words of certain foods. Work with him until he learns to say "Chicken nuggets please mom" (simple words. It's all about simple phrases at first. ALSO REMEMBER: autistic children are very picky eaters and will constantly ask for the same thing over and over (such as chicken nuggets.) If you find something he eats, keep feeding him that as long as it's healthy. And obviously you'll need to introduce fruits, vegetables, etc. When doing this, be sure to not let him leave the table until his plate is done as well, that's important in showing who's boss.
Having an autistic kid, you need to learn the basics of dealing with them properly. You can NOT treat them like a baby, or any other normal kid. They are not normal, and can't be treated like that and progress mentally , physically or emotionally. Once you get into a routine, it's easier. My mom used to make notecards with steps and pictures for each command. He had an index card on the mirror with steps on how to wash hands. He also had a book with pictures of the mouth, and each page had different teeth highlighted to show which area to brush.
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