Indeed parenting is not easy because as a parent you need to give your children the best information, not the best clothes. Anything a parent is telling their children, they need to be sure that is the right thing because those children will ask questions someday and if there is no good answer, they will start doubting you and that will make them seek for knowledge else where.
Love conquers all things! Don’t only try to gain permission to be a Christian from your dad, still look for a way to save him in love. It will be hard but it is possible. As Christian’s we know that the only way anyone can be saved is through Jesus Christ and nothing else but it’s hard convincing those who claim they know Christ not to mention those who don’t even believe in him at all but don’t worry about that, just share the gospel 🥰.