If you believe that everything the RCC purports to be the Gospel is in your catechism, then you are the one who should not be saying anything, my FRiend.
I do not believe that the Gospel of the Catholic church is the catechism. The Gospel is the Gospel of the Catholic church.
You’d know this too if you read a catechism.
I suggest you read one if you want others to take your assessment of Catholicism and it’s teachings seriously.