What does a tree or rock tell a pagan in Africa about Jesus Christ? What does a beautiful moonlit evening tell a Hindi about the Trinity, or the covenant of grace, or the indwelling Holy Spirit, or the age to come?
General revelation only confirms there is a God and so all men are without excuse before God. In order to know God truly and eternally, He had to condescend to bring truth and salvation down to man. This He did through the prophets of old and finally in the person of His son, Jesus Christ (Heb 1:1,2).
You will not find insulin, the technique for producing the polio vaccine, or detailed instructions for safe blood transfusion in the scriptures,
This all comes under the heading of common grace. God has created a world -- a universe -- that operates with certain unchanging laws. We can know and discover that world within the limits of the revelation given through that world.
But the God of the universe is not the god of pantheism. We cannot know anything infallibly by simply examining His creation since He has not chosen to reveal Himself personally to His people in that way.
General revelation and the laws of nature’s universe may help us find a cure for cancer, but they cannot help us find a cure for what truly ails us, a soul darkened by sin and misery.
Take away the infallible written Word of God and you would die in your sin. We all would.
Faith comes by hearing and hearing by the Word. The Word of God is not limited to an infallibly written media, but by His Providence He reveals His Word to us through faith in Him.