He has an impact related injury. He needs immediate attention. Get him to a vet.
Toss a towel over him and swaddle him up and put in a box. Keep him comfortable and he won't hurt you.
That's a full grown screechie.
They are quite dangerous and if you can handle it, then it is either injured or poisoned.
It needs to go to a vet immediately.
A GHO hen can kill you and won't even shed a tear.
Very docile if not threatened, but if they go into the M is for murder posture, your life is in danger, or over.