Look it up yourself; it used to be a "mortal sin" for a Catholic to eat meat on Friday.
Mortal sin doesn't automatically condemn some one to hell though. And any way, technically it STILL is a mortal sin to not preform a penance of some kind on Fridays.
It is up to YOU, not me, to prove your assertion.
I reason because you are unable to provide evidence of your assertion you do not have much of a clue as to what the Catholic Faith teaches.
Have a nice day