Hi, AuDHD parent of two autistic/AuDHD DC here. I'm also a former CAMHS ed psych.
All autistic children and adults are going to be unique. Life trajectories will be different depending on circumstances, co-occurring learning disabilities and conditions, etc. But here are some things I know to be helpful based on experience.
Accepting that your child is autistic is important. Not trying to pretend he's something he isn't. Denial isn't helpful - if this is difficult, try to get some support either via counselling or support groups to process your feelings. When DS is a bit older, he'll need you to help him accept his differences too. Doing the NeuroBears course together when he's primary age could be useful.
Autism is not anybody's "fault" - it's usually genetic. My family is a literal gold mine of undiagnosed high IQ autistics across several generations 😂
Connect with other SEN parents and groups who can help you navigate the school system, EHCPs, etc. This hopefully might allow DS to grow up around other autistic kids, so that he has the opportunity to develop friendships both with autistic and non-autistic children. I've met parents who wanted all their kids' friends to be neurotypical, but all this does is force children to mask and spend their lives in friendships where they're not understood, or they're tolerated and not really liked, or even bullied for their differences. Of course, he won't get on with every autistic child either, we don't all like each other just because we share a neurotype - but it's about the opportunity to have diverse interactions/friends.
Therapies and support can be helpful, but be careful what you choose. ABA is essentially conversion therapy that attempts to teach autistic children to behave in a non-autistic way. It's also incredibly time intensive and exhausting for them. There are kinder, more child led therapies such as AutPlay or filial therapy out there that can support with behaviour, getting social needs met positively (as opposed to just learning to perform neuronormative social skills) and those therapies involve parents and doing things at home. If there are sensory challenges, OT or sensory integration therapy may help.
Good luck - it may seem overwhelming now, but you've got this and will be the best person to help him navigate the world and advocate for him.