How do I make a Search&Destroy? [closed]

In Call Of Duty(COD) There is a minigame called Search&Destroy. It's where you have 1 life, 1 team has the bomb for 2 rounds, on the other team for the 2 rounds, they have the a thing where the enemy plants the bomb. It takes 10 seconds for the enemy to plant the bomb. Once they did, the game has 45 seconds left. And the other side has to defuse(un-plant) it. The next 2 rounds switches, the one who defends plants the bomb. That is what I want in my game. But I need help with it. If you answer, thank you.