Where does a Christian learn the basics of Christianity? Christian teachings come from the Scriptures. It's in the Bible, II Timothy 3:16, TLB. "The whole Bible was given to us by inspiration from God and is useful to teach us what is true and to make us realize what is wrong in our lives; it straightens us out and helps us do what is right."
Biblical doctrines or teachings are passed from believer to believer. It's in the Bible, II Timothy 2:2, TLB. "For you must teach others those things you and many others have heard me speak about. Teach these great truths to trustworthy men who will, in turn, pass them on to others."