You may be interested in the article by John Noe at https://www.prophecyrefi.org/about-us/the-millennial-maze/.When Christ rules everything will be different that it is now.
In the day that you are speaking of, there will not be a Supreme Court, or a UN or Congress. There will not be nations meeting to discuss the affairs of the world.
As I read the Scriptures it says to me that Jesus Christ will be the Supreme Ruler. HE will be the only one giving orders and those orders and directions will have no need of any approval or vote from anyone.
Then those same Scriptures tell me that just like the bodies of all the believers from the Old Testament era, David’s body will be resurrected, glorified, and reunited with his soul at Christ’s Second Coming and he will then serve as what we might think of as a “second-in-command” under Jesus during the millennial reign.
Then, Christ’s 12 apostles will sit on thrones with Him and serve as judges over the 12 tribes of Israel.
Then we can also know that Christians will reign with Jesus.
In Revelation 5:9-10, we read a quote that comes from twenty-four elders that John sees in heaven. These twenty-four elders represent the entirety of the church in heaven following the Rapture.
IMHO.....I do not find in the Scriptures that there will be any type of meetings which will decide the fate of people or any business to be done. Jesus Christ is the Supreme Ruler and we will be in a complete "THEOCRACY".
Human government has been a dismal failure. Our nation of America has probably been the greatest success of all efforts to govern society. Even this nation will continue to disintegrate as we approach the end. Most governments have made life unbearable for its subjects. Babylon under Nebuchadnezzar elevated human control over the masses to an art form. Bureaucracies were established to create a system of domination. You should notice how the church has become an extension of this same design. The “Shepherding/Discipleship” disaster (still strong) was a striking example. Jesus will set up a government that is righteous and just.
It raises a lot of issues and is worth reading.