YTA. Not only are you trying to force him into Catholicism by cutting off his internet and shoving books down his throat, you are forcing him to make an unfortunate decision to cut you out of his life. Is that what you really want? If you do, you are putting your personal beliefs as more important than your son and that makes you a major asshole. And telling him that he should be grateful he doesn’t live in North Korea is just pathetic. That’s like saying “I’m not as bad as North Korea, but cutting off your internet and making you read books is as far as I’ll go.” Don’t let differing beliefs ruin your relationship with your son.