zardaloop
I would suggest set all bullets to disabled at the start (bullet properties in sidebar) and enable them using events so you're sure there's nothing flying around when you don't need it. Of course you need at least 1 instance of the bullet object (or rocket in your pic) either in this layout or somewhere else in your project.
You can adjust all bullet parameters to make it arc even more
Angle of motion is different when facing left or right (you should know how to count degrees)
start at 0 degrees at right
counterclockwise is adding 1 degree
clockwise is adding -1 degree
360 degrees in 1 full circle
360 degrees same as 0 degrees
research on this if you're not a numbers person
Set Bullet's "Set Angle" to Yes (bullet properties in sidebar) to angle the sprite of the rocket similar to angle of motion
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