Hello, this link will show useful stats from this worlds: https://gol.gg/tournament/tournament-stats/World%20Championship%202019/
Do note that pro teams play champs thats are actually broken but solo queue players often fail with them because they do not understand why the champions are busted. Realistically, unless all of you have the time to play 6-8 hours a day and watch pro games, you may be better playing solo queue champions. Additionally, you should also understand what each comp is trying to achieve (poke and siege, pick, teamfight, split, etc.). Each player should understand the objectives in their own lane and what the team's objective is. Watching proplay, especially proview will be insightful for warding, rotating, and executing in lane.