After successfully reaching the fifth level in Pokemon GO, you can take control of the opponent's gyms or acquire your own gym and become its leader. Before entering the hall for the first time, you will be asked to choose a team.
There are three teams to choose from. Please note that the choice of a specific team does not carry any advantages or disadvantages over the others. As a last resort, just choose the team of your favorite color.
In order to become the leader of the gym, you need a team with a high level of Pokémon battle points and take control of the enemy gym, depleting its prestige to zero.
Before you try to take over the gym, it would be good to analyze it. If you have a Pokémon with a maximum of 500 Combat Points on your team, you will not be able to recapture a training room with more than 1000 Combat Points.
Before starting a battle, you must make sure that you have a mix of different types of Pokémon on your team and that your battle point level is higher than the average level of the entire opposing team.
The process of taking over a gym requires the participation of several of its members at once. In the beginning, you will have to fight with Pokémon with low Battle Points to reduce the prestige of the gym, but as you fight, you will encounter high-level Pokémon.
After defeating a member of the training hall, you will leave him and then challenge him over and over again, decreasing prestige each time you win a fight. After the prestige drops to zero, its level will turn gray, and you will be able to claim the place of the leader.
Another important thing you should keep in mind is that if you want to maintain your leadership status, you need the Pokémon with the highest Battle Points of any other member of the gym.