My child is 7, so no advice from the perspective of being a parent to an adult child.
However, I am an adult who (while undiagnosed) is highly suspected to be autistic. This wasn't picked up by my mum when I was younger (I'm 27 now) because in girls, autism usually manifests differently and she thought I was just particular with how I liked things. So I'm going to tell you things from my perspective.
My secondary school years were the worst. Being bullied, being too burnt out (though this was seen as depression) to attend school but having to anyway. Spending my last year skipping school and consequently failing most of my exams (though I was never very academic and I'm still not). Had my son at the age of 20, and really really struggled because I hadn't even thought of myself being autistic (thought I was just depressed). It wasn't until my sons school referred him for an autism assessment in year 1 (he's now in year 3) that I even considered I could be autistic.
I moved from my home city to Manchester in 2020, with my son, just before the first lockdown went into effect. I flitted between 3 different jobs in 3 years, and ended up having a mental breakdown and moving back in with my parents in 2023. I do not think I can ever live on my own (away from my mum) and I will probably never be able to work (I've worked office jobs, customer-facing roles, I've been a care worker, I've worked part time and full time and everything has left me burnt out and becoming physically unwell from said burn-out to the point I've ended up having to just quit multiple jobs because I became suicidal). In my whole life, I've probably worked about 7 or 8 jobs and have quit them all within months of working there because they got too much for me.
So yeah, at 27 I still live with my mum and my son. And people criticise me for that but they don't see the things I struggle with on a daily basis. I know my truth and so does my mum.
I struggle with food. I basically live on bread, crisps and takeaways because trying new food is so hard for me that I gag and cry whenever I do try. I lack common sense and I'm very naive.
Saying all of that, I have my strengths. I am extremely empathetic to people I care about, I am calm in other people's crisises (crises?), I am a good problem solver and I can find joy in pretty much anything. When I was able to work, I dedicated all my time and energy to learning about that job. When I wasn't burnt out, I was one of the most efficient workers on each team I joined. I have also managed to have a mortgage (when I lived in Manchester) with my then-partner.
For all my struggles, I have my strengths. I would recommend working on your child's strengths (which I'm sure you're already doing) and encouraging them to work on the things they struggle with. Some things they'll build up a tolerance for, some they won't. And that's okay. Tell them you love them exactly the way they are.
I know a lot of my post seems to be focussing on the negatives, but I am trying to show that while I have struggles, I also exceed in some areas of my life. And it is possible to have a fulfilling life with autism, even if a little extra effort needs to be put in.