If its proven beyond a reasonable doubt that he is the shooter, or was involved with the murder in any other way, he is facing several decades or even life in prison for the murder of UnitedHealthcare+CEO+Brian+Thompson.
For any young guy going into the big house for the rest of his life, he will likely be heavily used and abused by the very hardened convicts.
He will be their plaything and party toy, but at the end of the day, he will just become another prison boy.
His trial for taking the life of CEO+Brian+Thompson will likely reveal his motive.
https://thedigitallabyrinth.blogspot.com/search?q=Luigi+Mangione