Sorry brother for the death of your brother but you can't do anything to help him now because he is death and there is no repentance in the grave. And his action of suicide shows unbelief and faithless.
The only person in the New Testament who committed suicide was Judas Iscariot who betrayed JESUS CHRIST. Now, let us listen carefully to what JESUS CHRIST our PRECIOUS LORD said about him, “The Son of Man goes as it is written of Him, but woe to that man by whom the Son of Man is betrayed! It would have been better for that man if he had not been born (Matthew 26:24.)”
The WORD of GOD our GRACIOUS FATHER, tell us clearly where murderers will go. For it is written, "He who overcomes shall inherit all things, and I will be his God and he shall by My son. But the cowards, faithless, detestable, murderers, sexually immoral, sorcerers, idolaters, and all liars--their share will be in the lake that burns with fire and sulfur, which is the second death (Revelation 21:8)."
Again it is written, "“Now the works of the flesh are evident, which are: adultery, uncleanness, licentiousness, idolatry, sorcery, hatred, contentions, jealousies, outbursts of wrath, selfish ambitions, dissensions, heresies, envy, murders, drunkenness, revelries, and the like; of which I tell you beforehand, just as I also told you in time past, that those who practice such things will not inherit the kingdom of God.” (Galatians 5:19).
The Word of GOD says we must persevere to the end in order to be saved, Mark 13:13. Or Hebrews 3:14: “We have come to share in Christ, if indeed we hold our original confidence firm to the end.” That is a very serious warning
Yes, there are people now in hell. All those who do not believed in JESUS CHRIST the Son of GOD are in hell.
The Lake of Fire is the final place for eternal punishment and for now, there is no one there. For it is written, " Then I saw a great white throne and him who was seated on it. From his presence earth and sky fled away, and no place was found for them. And I saw the dead, great and small, standing before the throne, and books were opened. Then another book was opened, which is the book of life. And the dead were judged by what was written in the books, according to what they had done. And the sea gave up the dead who were in it, Death and Hades gave up the dead who were in them, and they were judged, each one of them, according to what they had done. Then Death and Hades were thrown into the lake of fire. This is the second death, the lake of fire. And if anyone's name was not found written in the book of life, he was thrown into the lake of fire (Revelation 20:11-15).”