Hello, and welcome.
I only got diagnosed last year when I was 22, so when I was little we didn't know exactly what the problems were or how to deal with them.
So, I wish my mom could have understood my sensitivities, bright lights, bad smells, and textures. I was a picky eater, but it just wasn't about not wanting to eat vegetables, I couldn't stand the textures of certain foods. And to this day my family still doesn't understand how much I hate the smell of bananas, it's one of the worst smells in the world to me. If someone's eating a banana in the kitchen, I can smell it in my room, ugh.
My mom was always trying to get me to go outside, and to stop playing my video games. I wish that she had understood two things. One, that video games were, and still are, my obsession and that I'm very interested and invested in them. And number two, that the sun hurts my eyes, and makes my skin feel itchy and like I'm burning.
I would have liked accomodations in school. Such as choosing where to sit, and getting help with schoolwork. I was too quiet and shy to ask for help. I would have meltdowns when I didn't understand the homework and couldn't complete it. My mom tried to help me learn the material and got me tutors, but I didn't like meeting new people.
Also, my family thought that my shyness was a phase and that I would eventually grow out of it. But alas, I'm am still shy, quiet and socially awkward, although doing slightly better.