This will come up when you land on a Railroad Tile. Often, you will get a chance to attack the property of other players (Shutdown minigame) and take some money from them via the Bank Heist minigame as well.Just like the original game, you can build Hotels and Houses in Monopoly Go as well and upgrade them as you keep playing.You can unlock properties with the money you’ve collected. As you keep moving ahead, you will earn in-game money, various rewards, and fun things based on the tile you have landed on. Your goal as the player is to roll a die to move your Token ahead on the Monopoly Go board.
If you are just starting out with the game, take a look at the basics of gameplay right here