I am out the other end of childhood with a son in his early 20s. But yet to navigate adult hood.
As someone says, it definitely gets different!
My advice is that you can't properly support your son unless you are in the right frame of mind. So finding time to get a bit of time for yourself as often as possible is very important.
Assuming you have a partner, it is very important you are both singing from the same song sheet - mixed messages are to be avoided.
Do your best to keep your son as calm as possible, however that may be. You may have to ignore advice to get your child out on a daily basis to play parks, soft play etc. My DS was definitely calmer and more rational on days when he was at home playing with me or his toys. Home became his safe space, and however much destruction had been wrought elsewhere, he knew at home it was calm and safe. That didn't mean I ignored stuff, but I took the view that unless I was actually called in for something serious, what happened at school stayed at school.
Communication is important. He is still young so his speech and ability to explain will improve, which will help. Always talk to him about why he finds some things hard and how he feels. Encourage him to talk about it, my son used to tell me it felt like his brain was on fire and about to explode.
Learn what triggers him and develop strategies to work round and avoid the triggers.
It's hard work parenting these children. My DS was adopted and the best bit of advice from the SW was don't aim to be a perfect parent and do a perfect parenting job, that is impossible. Just aim to be adequate. That's all that is needed.