Another thing I don't know what to think of in religion is the idea that everyone deserves to go to hell.

So basically all humans deserve to be tortured mercilessly forever and ever when we die is what that means. Does that include children as well? If not, what age do children start to deserve to be tortured endlessly? Is it when they become adults at 18 they start deserving it, or is it at a younger age maybe teen/preteen?
I'm sure people will say that's up to God. But what's your opinion on the matter?