Someone was asking about how to shoot BULLETS on left and right side too. The only way I have found is this way at the moment. I hope it might help that's why I am writing this tutorial. CAPX is uploaded as well.
1 Create new project and call it as you wish
2 Add background and lock it.
3 Add main layer
4 Add tiles for platform and make it solid
5 Add player and give it pin behavior
6 Create small box any color and name it Playerbox
7 Create Bullet
and Lay it out like this below
Now open Events and add this code
This should work good luck