Let us bring your request to God, Anonymous, and let's pray for the salvation of your brother. The Bible tells us in Romans 10:17 WEB that, So belief comes by hearing, and hearing by the word of God. Hearing worship music that glorifies God can help do this.
It is wonderful that you desire for your younger brother to gain a passion for worship music. Remember we are told to, Be filled with the Spirit, speaking to one another in psalms, hymns, and spiritual songs, singing and making melody in your heart to the Lord. Ephesians 5:18,19 WEB.
Let us pray together. Father, we ask for your will to be done in this situation. We ask that you would instill in our brother a deep desire to listen and enjoy worship music that glorifies you. We ask that you would bring him to salvation and that he would believe in Jesus Christ as Lord and Savior. We ask that he would confess with his mouth that Jesus is Lord, and believe in his heart that God raised him from the dead. We ask that he would be saved as we are told, because with the heart one believes resulting in righteousness; and with the mouth confession is made resulting in salvation. And there is no other name by which we can be saved says the Lord. For whoever will call on the name of the Lord will be saved. We ask this in Jesus Christ Name.
While you wait on God's answer, continue to model a life of worship for your brother. Let your attitude towards him be motivated by love. Pray for his salvation and that he would worship God in all areas of his life and to be a follower of Jesus Christ.