angelamarie, your father will eventually accept the Truth if you do.
The Truth you want your father to believe is to be united to the True Church in some way in order to save our souls. Novus ordo the new religion has gone astray, much like the Protestants did years and years ago. The Protestants did not suddenly change the names of their Churches, much like Vatican II didn't, it took a long time for them to change the name, for years the Protestants still thought of themselves as catholic, at least the lay people did.
Many died in the new Protestant religion and only God knows what happened to their souls.
If you take the necessary steps to find Christ's church, "Seek and you shall Find", so will your father, after many prayers from you.
When I realized the novus ordor made a wrong turn, I turned back knowing if I didn't all my loved ones would continue on the path of destruction. I was right, one by one, they came back, little by little, at least my parents, and a few others.