The point is that "back in the day" you went to hell if you ate meat on any Friday and didn't fast and abstain on Ash Wednesday and Good Friday.
You didn't get a choice about it, it was a church law.
Your voluntary penance had to be something in addition to that.
You'll see the link I posted is to the Code of Canon Law. It's still "the law".
As to whether or not one is going to Hell, the "law" doesn't speak to that. Someone may have told you that for some misguided reason but I believe the Church has always recognized that there is only one Judge of the living and the dead.
I could be wrong, perhaps there is indeed a citation somewhere showing that the Church has stated definitively that someone would go to Hell; no ifs, ands, or buts.