General Revelation is the revelation of God and right and wrong that is revealed from nature. It is known by all.

• Rom. 1:18-20, “For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who suppress the truth in unrighteousness, 19 because that which is known about God is evident within them; for God made it evident to them. 20 For since the creation of the world His invisible attributes, His eternal power, and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse.”
• Rom. 2:14-15, “For when Gentiles who do not have the Law do instinctively the things of the Law, these, not having the Law, are a law to themselves, 15 in that they show the work of the Law written in their hearts, their conscience bearing witness, and their thoughts alternately accusing or else defending them.”

General Revelation does not provide enough information for salvation because it is obscured by the sinfulness of mankind. This is why Special Revelation is needed.