In the soda fizz levels, whenever you combine a candy in the soda, a fizz (bubble) will show up on the candy
When you combine a candy that already has a bubble, another bubble will appear on the candy. The goal is to keep combining the candies until you get 4 bubbles. Once you get 4 bubbles on one candy, all the other candies of the same colour will get another bubble
you need to create a chain reaction where you can get 6 candies in a row to reach 4 bubbles. Once you get the chain reaction, you will be rewarded with a soda cap. Congrats!