You must be born again to become a child of God. You must be born of the Spirit of God and of water, through baptism as Jesus commanded.
The first man, Adam was made by God. He was a son of God, until he sinned and was cast out of Paradise. Since then the offspring of Adam were not children of God but sons of men.
Jesus Christ was the second Adam, born of a women but of the Spirit of God, not of the seed of a man. He was born of God and He did the will of God. He is the Son of God.
Those who believe in Jesus, accept and obey Him, repent and are baptized in water, become born of the Spirit of God. They become children of God, sons of God, but if they sin, like Adam they will be cast out and will not enter heaven.
We read in John 1:12,13 "12But to all who did receive Him, to those who believed in His name, He gave the right to become children of God— 13children born not of blood, nor of the desire or will of man, but born of God.
Jesus said:"He who is of God hears the words of God; John 8:47.
He said:27“My sheep hear My voice, and I know them, and they follow Me; 28and I give eternal life to them, and they will never perish; and no one will snatch them out of My hand. John 10:27,28.
"No one who is born of God practices sin, because His seed abides in him; and he cannot sin, because he is born of God."1 John 3:9
"For whatever is born of God overcomes the world; and this is the victory that has overcome the world-- our faith."1 John 5:4.
You must be born again to enter the kingdom of heaven. Jesus said:"I say to you, unless one is born of water and the Spirit he cannot enter into the kingdom of God."John 3:5.
Have you been born again? Have you believed in Jesus, repented and been baptized as He commanded? Have you received the Holy Spirit that He promised to those who obey Him? Do you hear the words of God? Are you one of His sheep? Do you hear His voice? Do you follow Him? Have you stopped sinning? Do you overcome the flesh and the world? Are you truly born again of the Spirit of God?
May Jesus bless you.