To play Ludo star league you have to be Level 4. Once you reach Level 4 in the game and won 1 game, you reach BRONZE League.
After you are in a league, then you will have to win public games (1 on 1, 4 Player, Team-up) to increase your ranking in the league. When the league competition ends the top 20% (Top 40 people) will be upgraded to the next higher league.
Also you can go through this tutorial video to understand about the league in detail: link
After you are in a league, then you will have to win public games (1 on 1, 4 Player, Team-up) to increase your ranking in the league. When the league competition ends the top 20% (Top 40 people) will be upgraded to the next higher league.
Also you can go through this tutorial video to understand about the league in detail: link