Bounce It! is a hyper casual game in which your main objective is to bounce the balls into one of the four baskets placed on both sides of your screen. If one ball falls into the abyss bellow, you loose a level. Do not worry, you will have a few platforms that should prevent the balls from falling right away, but they break easily, so be careful.
As you progress through levels, different ball types appear so you never truly get used to the weight of it all. Try and reach level 10 if you can.