Cat Mario is just like Super Mario with little changes in it. In Cat Mario player plays the whole game as a white cat. In this game all you have to do is to survive till the end of level by not falling into pits or by not getting killed by the enemies.
The player loses his one life or one chance if he falls in the pit or touches the enemy or if any brick wall falls on Catís head. So player have to protect the cat from these three obstacles to survive till the end of the level.
The game should be played using arrow keys. The left arrow key, which will move cat to the left, same way right arrow key is to move cat to the right and to jump, player has to press up arrow key.
You will learn more once you start playing on your own. Enjoy the game.