Autistic son..

My step son just got diagnosed with autism (level 1), ADHD, ODD and TIC disorder last Thursday. I started homeschooling him and his 3 siblings last Fall and I feel so overwhelmed with his diagnosis. He can’t really read or write but math is fine. We’re going to start occupational therapy within the next week or so but my question is how am I suppose to teach him to read/write? I know therapy will basically only teach him how to manage his emotions and help with everyday life and not so much schooling. Any advice is appreciated! Is homeschooling the right thing to do for him or would a public school have more resources for him? Thanks