Hi, my name is mamaneedingadvice! are there courses I can take to help my son?

Hi I'm lucky enough 2 have a son & daughter (13yrs age gap) my son is miracle I never thought I'd have as lost my first daugher at birth then years if I've for my daughter. When Dr who had told me I was pre menopause suggested hospital. I remember this day with huge fondness as thought my cervical cancer was back but my boy was on scan @ 5months. He had a horrendous induction which left him with the need for oxygen & as I later found out he had been resuscitated too as had gone just under 4mins without oxygen. I knew they were blocking me seeing him but I remember his small blue bofy being moved away awaiting his cry. We had lots of scans as told me my placenta wasnt feeding him after B/F him & giving him food he was diagnosed with so many allergys so had to change his diet but At 2 Yr check health visitor told me she had concerns from his 1st year check which he failed both. I fid everything eye/hearing tests just after his 2nd birthday he was diagnosed with non verbal ASD & ADHD & that umbrella term of severe complex needs.(I opted for blood test turns out they were right) but I love him so much & He's a bright happy little boy, unless he's had a bad day at so called specialist school (another story just 2yrs fighting L/A who refused him this school even after school board passed him) he isn't aggressive to anyone but himself which is heart breaking & I try to step in when he will allow me if not lay him on padded play mat until he regulates. Any advice for helping him would be really helpfull. He's 7 now & knows what he wants but gets frustrated if I font understand. The school don't share anything other than daily routine (I requested p.e.c.s that I could use at home or a site thst sold same they use but feel school definitely withhold information) He's been bitten numerous times I only get told if there's a mark when he leaves no accident forms ect. Feel like fought so hard at tribunal to get him in this school which apparently best there is. I was wondering as school won't give me any homework gir half terms or short bursts over weekend if there are any courses I could take to help me better assist my Don & hopefully find a way of him communicating his needs. I apologise know very long but am a desperate single mum with no support network stuck in a village which isn't best (currently trying to downsize as paying bedroom tax on a room not needed when could go on my don) sorry my anxiety causes me to not write well or make subject shorter. Fir anyone thar read this all your patience is incredibly as know my anxiety to ensure my son has everything he needs leads me to go off. If anyone has any recommendations I'd be so greatfull. I hope you have a great day & thanks for reading this mamouth message.